Savoy » My iPhone is not a Mac Pro
http://savoysoftware.com/blog/?p=114

This article is about enhancing the performance of iPhone applications using the power of Objective C++. By discussing a real-world problem from Savoy’s Spots application, the article shows the necessary optimizations to make the program run smoothly in three steps.

Using Objective-C++ on the iPhone application "Spots" to achieve acceptable performance in an intensive graphical application.

The Case of the Slooooow System

Dynamic scaling is better than auto scaling in the cloud - George Resse

Good rant about why auto-scaling is not dynamic scaling: two of the most widely cited advantages of the cloud. Not entirely convinced by the argument, though. I suspect governors can be used to manage scaling in a sensible way.

Sometimes traffic is truly unexpected. But not as often as you think. If you know you are getting coverage in some publication, marketing should have done an ROI projection on the campaign and be able to provide you with expected response rates. But you don't want it to auto-scale. Auto-scaling cannot differentiate between valid traffic and non-sense. You can. If your environment is experiencing a sudden, unexpected spike in activity, the appropriate approach is to have minimal auto-scaling with governors in place, receive a notification from your cloud infrastructure management tools, then determinate what the best way to respond is going forward. Here, the auto-scaling is simply a band-aid to enable a human to use dynamic scaling to define an appropriate, temporary capacity to support the unexpected change in demand. If you know you have a batch window from midnight to 3am, set your cloud infrastructure management tools to add capacity at 11:30 and throttle back at 3:30.

Makes good sense. I'd probably disagree on a few points if the cloud is owned/controlled by one's own organization.

config.trim_on_minimize

founded by Google. Quote: is an open, distributed server platform for researchers to deploy Internet measurement tools.

google isp test speed network neutrality

parámetros de la bazofia de la máquina virtual del puto java

increasing speed of Apple

Apple Inc. hasn't done much talking about Snow Leopard, the next-generation update to Mac OS X that's due to be released in 2009 (possibly within the first quarter of the year). But in what came as a surprise to many, the company has said that the new operating system will contain a limited number of new features.

It seems clear that Apple's biggest focus with Snow Leopard is slimming down and speeding up its flagship operating system -- both of which are attractive to any computer user. But why wait until Snow Leopard ships? There are a number of ways you can slim down and speed up your machine right now.

The SHOP.COM Cache System is an object cache system that...

Perf4J is a set of utilities for calculating and displaying perfomance statistics for Java code. For developers who are familiar with logging frameworks such as log4j or java.util.logging, an analogy helps to describe Perf4J: Perf4J is to System.currentTimeMillis() as log4j is to System.out.println()

Perf4J

Java performance tool

サイトをもっと速くしたいと思ったときに、サイトを最適化して表示速度を速くしてくれる、使えるツールいろいろとまとめ from Design Walker[http://www.designwalker.com/2009/01/speedup.html]

いろいろあるなぁ

Sizzle (new selector engine, available separately), Live Events (a variant of event delegation), Feature Detection (instead of user agent sniffing), faster HTML injection and more.

January 14th, 2009: The jQuery team is pleased to release the latest major release of the jQuery JavaScript library! A lot of coding, testing, and documenting has gone in to this release and we're really quite proud of it.

<3<3<3

The lesson, Marissa said, is that speed matters. People do not like to wait. Do not make them.

On the web, speed matters. I see it with campaigns all the time.

This conclusion may be surprising -- people notice a half second delay? -- but we had a similar experience at Amazon.com. In A/B tests, we tried delaying the page in increments of 100 milliseconds and found that even very small delays would result in substantial and costly drops in revenue.

at Yahoo! User Interface Blog

Image optimization tips

glasnost, search engine

Community-based diagnostics. Early stages.

Javascript performance book

Gekauft und nicht bereut!

Learn everything you need to know about Scaling your Rails app through 13 informative Screencasts produced by Gregg Pollack with the support of New Relic.

Nice Screencasts series of performance and scalability of Rails Apps by Gregg Pollack

Scaling Rails screencasts produced by Gregg Pollack and supported by New Relic

Joe Stump, Lead Architect at Digg, gave this presentation at the Web 2.0 Expo. I couldn't find the actual presentation, but fortunately Kris Jordan took some great notes. That's how key moments in history are accidentally captured forever. Joe was also kind enough to respond to my email questions with a phone call.

Scaling Strategies

JSLitmus

A lightweight tool for creating ad-hoc JavaScript benchmark tests

JSLitmus is a lightweight tool for creating ad-hoc JavaScript benchmark tests. Features include ... * Single-file install (JSLitmus.js) * Works on Firefox, Opera, Safari, IE, Google Chrome, and iPhone browsers * Adaptive test cycles - tests take ~1-2 seconds, regardless of the operation * Google Chart + TinyUrl integration * Open Source MIT-style license (see source)

JSりとます：JSパフォーマンス計測ツール

This document will focus on optimizing code to run faster. However, as you will see later, doing this may involve having to optimize the code in a different aspect. Furthermore, often when programmers are trying to optimize one aspect of a program, they are doing so in order to increase speed.

tuning tips

DBのチューニング

なるほど便利そうだ

Sprockets is a Ruby library that preprocesses and concatenates JavaScript source files.

"Serve lots of little JavaScripts as a single file."

HTTPの通信状況をデバッグ

ウェブサイトを高速化するにあたり、そのフロントエンド処理に着目し、処理効率の向上に役立てることのできるティップスやツールを紹介する。 - builder by ZDNet Japan

Rails Performance Resources - Expert advice on tuning and optimizing your Rails app.

primer on ruby

ここ数年のPostgreSQLの進化はすさまじく、2009年現在においてその性能はOracleと同等かそれより速い。

postgresqlを使う時に読み返したい

ケータイ大規模サービスの開発・運用に関する資料のまとめ

Interesting article about MySQL scalability problems.

on-building-a-stupidly-fast-graph-database

connected to and things that connect to them. These are symmetrical — so creating a link from item A to item B, creates a reference from item B to item A.

Video and slides from Feb 2009 presentation at Google on trends in Javascript performance, web applications, making use of higher performance, stateful browser clients.

reads like The not so far Future of the Web. Great.

YSlow

aid, here is what it takes to do 10.000 gets and sets:

Read Later

99 trucs pour accèlerer Vista, du bon et du moins bon ...

昨日のの邦訳

"Database sharding is the process of splitting up a database across multiple machines to improve the scalability of an application. The justification for database sharding is that after a certain scale point it is cheaper and more feasible to scale a site horizontally by adding more machines than to grow it vertically by adding beefier servers."

SELECT Name, Address FROM Customers WHERE CustomerID= ?", conn);

With jQuery 1.3.2 out the door I've been looking for more ways to profile and optimize jQuery. Previously I did a survey of jQuery-using sites to figure out which selectors they were using. This led to the construction of the new Sizzle Selector Engine which targeted those selectors for improvement. Additionally, I constructed a deep profiling plugin for jQuery which helped to spot methods that were taking a long time to run in live jQuery sites. This helped bring about the improvements in jQuery 1.2.6, 1.3, and 1.3.2.

Programatically profile functions, allowing you to analyse the output easily and pinpoint bottlenecks.

Utilidad online para probar la carga de un website, hace un test para probar la respuesta del site por encima de 40 clientes conectados

testt website - cool tool

Slow websites means lost customers and revenues. Be proactive and find out the performance limits of your website before you learn it the hard way. Load Impact is an online load testing service that lets you load test your web site with just a few mouse clicks.

Active record memory cache.

A Write-Through Cacheing Library for ActiveRecord

class Message < ActiveRecord::Base

InfoQ: Rockstar Memcaching http://www.infoq.com/presentations/lutke-rockstar-memcaching performance presentation

About the conference RubyFringe is an avant-garde conference for developers that are excited about emerging Ruby projects and technologies. They're mounting a unique and eccentric gathering of the people and projects that are driving things forward in our community.

Memcached tutorial video from the RubyFringe conference.

Video of memcached best-practices

RubyFringe presentation on Memcached

tobias lutke rubyfringe talk about memcached

How To Diagnose a Suddenly Slow Windows Computer? -- article related to Ask Slashdot, Windows, and IT.

%D リクエストを処理するのにかかった時間、マイクロ秒単位

Apacheのマニュアル読めってこと

CollegeHumor

CollegeHumor memcache use

カーネルメモリの設定を変更する

やってみた

停止するサービスなど

web design

"These rules are the key to speeding up your web pages. They've been tested on some of the most popular sites on the Internet and have successfully reduced the response times of those pages by 25-50%."

minimizing and optimizing javascript files in a ruby project for deployment

java

For best performance, CSS and JavaScript should be served up using as few requests and bytes as possible. Juicer is a new command line tool that helps by resolving dependencies, merging and minifying files. It can even check your syntax, add cache busters to and cycle asset hosts on URLs in CSS files and more.

Juicer - a CSS and JavaScript packaging tool For best performance, CSS and JavaScript should be served up using as few requests and bytes as possible. Juicer is a new command line tool that helps by resolving dependencies, merging and minifying files. It can even check your syntax, add cache busters to and cycle asset hosts on URLs in CSS files and more

Interesting comparison of JSON and homebrewed control-char delimited data.

This widget downloads a list of all of your contacts, in JavaScript, in under 200ms (this is true even for members with 10,000+ contacts).

ere’s an Elephant in the Ro

I spent more time working on SSDs that weren’t the X25-M than the Intel drive itself. The Intel drive just worked as it should, the rest of them didn’t.

Fascinating article on SSDs. Until now, I have been aware of SSDs but largely ignored them due to cost-per-gigabyte for this heavy-duty data user. They're starting to get interesting. I doubt my _next_ drive will be an SSD, but the one after that probably will be. Given these sequential read/write numbers, I do look forward to putting my Aperture library on an SSD.

Best article about SSD technology ever written.

# nt a better summary of heap statistics. # Sort objects by retained heap. In other words, some tools can tell you the memory usage of an object and all other objects that are referenced by it, as well as list the objects referenced by other objects. This makes it much faster to diagnose the cause of a memory leak.

How to Fix Memory Leaks in Java | Javalobby

thorough tutorial on identifying and fixing memory leaks, focused on Java

Recently, I bought a new USB flash drive and wanted to know whether the specs matched up to what it can actually do. Usually these days most USB flash drives

In this article I am going to tell you how to decrease firefox memory usage and increase firefox speed. This article of mine has two parts. So, follow each part to the end to make your Firefox Faster and Reduce your Firefox Memory Usage:

Mempercepat firefox

If I couold be bothered...

understand my meaning better I have taken picture of my deskto

We are on the edge of two potent technological changes: Clouds and Memory Based Architectures. This evolution will rip open a chasm where new players can enter and prosper. Google is the master of disk. You can't beat them at a game they perfected. Disk based databases like SimpleDB and BigTable are complicated beasts, typical last gasp products of any aging technology before a change. The next era is the age of Memory and Cloud which will allow for new players to succeed. The tipping point is soon. Let's take a short trip down web architecture lane: # It's 1993: Yahoo runs on FreeBSD, Apache, Perl scripts and a SQL database # It's 1995: Scale-up the database. # It's 1998: LAMP # It's 1999: Stateless + Load Balanced + Database + SAN # It's 2001: In-memory data-grid. # It's 2003: Add a caching layer. # It's 2004: Add scale-out and partitioning. # It's 2005: Add asynchronous job scheduling and maybe a distributed file system. # It's 2007: Move it all into the cloud. # It's 2008: Cloud +

What makes Memory Based Architectures different from traditional architectures is that memory is the system of record. Also discussed Jim Starkey NimbusDB

Performance is a key factor for any successful website. And since WordPress is becoming more popular than ever, it will only be at its best when raised in the

13 Great WordPress Speed Tips & Tricks for MAX Performance

Fix Memory

great bookmarks

How to Fix Memory Leaks in Java

Plus a nice comment from Zed.

config.trim_on_minimize

about:config

go fast do less

人文とは人間が活字を文章として廃絶する人糞。読み返しては加筆・修正を繰り返し日々進化する“βログ”。連想用日本風土派生図に基づき、政治・経済・メディアから様々な戦略や策略を読み解き、チラシの裏に真剣に書き記す。

C:\Documents and Settings\<User Name>\Application Data\Mozilla\Firefox\Profiles\<Random>.default

こんな方法があるという。

urlclassifier3.sqliteに注意！

urlclassifier3.sqlite を消すとか。

more application frameworks need a page like this. how to make it go. - added by harper reed's google reader

Really good talk summarizing Django best practices.

おまけ： Sharding

Web屋のネタ帳さんの記事では16のポイントが紹介されているが、漢（オトコ）のコンピュータ道の記事は10の方法だったのであと6つ足りない。オトコは数で勝負！！というわけで今日はネタを振り絞ってさらに7つのMySQL高速化テクニックを紹介しよう。

さらにMySQLを高速化する7つの方法

perfomance and scalability testing of a website

stress test your web app

What is Tsung ? The purpose of Tsung is to simulate users in order to test the scalability and performance of IP based client/server applications. You can use it to do load and stress testing of your servers. (Definition coming from the Tsung website) In this post, I will introduce the use of Tsung in order for you to stress test your web applications. Why Tsung ? Because it’s an Open-Source project and, to tell the truth, mainly because this application has been coded in Erlang which gives Tsung a little advantage on the other tools: it has the potential to simulate A LOT of concurrent requests … without crashing. That’s what we expect from a stress testing app, isn’t it? Let’s start the installation We will need the Perl Templating-Toolkit and the Gnu plotting utility in order to create nice HTML and graphical reports with the result data set. So, back to your command prompt: ~$ sudo apt-get install gnuplot-nox libtemplate-perl libhtml-template-perl libhtml-template-expr-pe

ウェブアプリケーションのパフォーマンステスト用ツール Tsung の使い方

Google's Python engineers have launched a new project called Unladen Swallow that seeks to improve the performance of the Python programming language. One of the project's goals is to replace the Python virtual machine with an LLVM-based JIT.

Google's Python engineers have launched a new project called Unladen Swallow, which aims to bring a major performance boost to the Python programming language by making runtime speed five times faster. The project is being implemented as a branch of the conventional CPython runtime and will be fully source-compatible with regular Python applications and native extensions. This will make it possible to eventually merge the improvements into Python trunk. The goal of the Unladen Swallow project is to use LLVM, the Low Level Virtual Machine compiler infrastructure, to build a just-in-time (JIT) compilation engine that can replace Python's own specialized virtual machine. This approach offers a number of significant advantages. As the developers describe in the project plan, the project will make it possible to transition Python to a register-based virtual machine and will pave the way for future optimizations. Adopting LLVM could also potentially open the door for more seamlessly integr

Google's Python engineers have launched a new project called Unladen Swallow, which aims to bring a major performance boost to the Python programming language by making runtime speed five times faster.

don't blame the rounded corners! Yahoo! F2E Summit 2008

Performance Video

Cachr

"Facebook will complete its roll-out of a new photo storage system designed to reduce the social network's reliance on expensive proprietary solutions from NetApp and Akamai."

Unlimited Novelty

How many of Twitters issues caused by succumbing to NIH (Not Invented Here)

In-depth discussion of message queuing systems and systems architecture, with Twitter representatives speaking up in the comments thread.

Long, but very interesting analysis of ruby, message queue systems, and Twitter's use thereof

twitter and ruby

http://www.tervela.com/tmx

Keeping your database simple and fast is often difficult if you use higher level frameworks such as ActiveRecords in Ruby or Java object persistence technologies such as Hibernate. There is a lot of magic that is happening out of sight that you have no control over. If you then have to scale your application it is often the relational database that these technologies require that becomes the performance and scaling bottleneck. Often requiring complex custom implementations of partitioning and sharding to make it work. The AWS services Amazon S3 and Amazon SimpleDB were designed to handle the dominant storage usage patterns within Amazon and they greatly reduced our need to rely on relational storage for scaling our systems. But it is almost never the case that a single storage technique is used in applications and services that need to operate at enterprise scale. For example it is a common pattern that objects stored in S3 using a primary key, have a collection of secondary keys (e.g

allthingsdistributed.com allthingsdistributed.com Database DatabaseSimpleandFast

The bottomline is: use LINK instead of @import if you want stylesheets to download in parallel resulting in a faster page.

facebook structure

Different registry tweaks to do random things. Encryption etc.

外部スタイルシートの指定は@importとlinkでどちらがいいかと、書籍「ハイパフォーマンスWebサイト

そうやねんけど@import以外でやるとメンドイしなぁ管理

Going forward the performance community needs to partner more with browser vendors in addition to our more typical black box experiments. Browser makers know what is costly or irrelevant in terms of performance. Opera lists repaint and reflow as one of the three main contributors to sluggish JavaScript, so it definitely seems worth a look.

What causes reflows and repaints. These days usually not a big deal on websites targeted at regular PCs, but could be applicable to mobile devices.

"A repaint occurs when changes are made to an elements skin that changes visibility, but do not affect its layout. Examples of this include outline, visibility, or background color. According to Opera, repaint is expensive because the browser must verify the visibility of all other nodes in the DOM tree. A reflow is even more critical to performance because it involves changes that affect the layout of a portion of the page (or the whole page). Reflow of an element causes the subsequent reflow of all child and ancestor elements as well as any elements following it in the DOM."

<draco> http://service.futuremark.com/peacekeeper/index.action interesting concept, but I think their testing methodology is slightly forced/false

Teste de desmpenho de navegadores

The Browser Benchmark by Futuremark Corporation

Find out which is the fastest browser on your system with Peacekeeper, the browser benchmark from Futuremark. Peacekeeper measures browser speed with a wide range of JavaScript tests and displays the results in an easy to understand format.

Où l'on voit apparaître le verbe "to desugar"

PHP Quick Profiler

In our company, code reviews play an integral part in the development process for making quality software. We opt for a mentor style approach with Wufoo, where a developer works on a segment for a period of time and then passes it up to a more experienced developer for review. We really like this approach because it means more developers become familiar with the foundation of different code level services. More importantly, they act as an additional safeguard against security holes, memory leaks, poor queries and heavy file structures. Unfortunately, these reviews are also very time consuming and in a small team can sometimes be an inconvenience to the reviewer — another developer with their own todo list to accomplish.

PHP Form Performance

actionscript actionscript3

Actionscript Flex Optimization

画像はえー。

A method of using XHR requests to get chrome from the server rather than fetching it as the inital HTTP GET.

Nginx + php.

googleのサーバーは一台ごとにバッテリーがついていて、1160台１セットでコンテナに収まっている。

Unresolvable

Googleサーバで非常に驚くのは、サーバ1台1台が、それぞれ12Vのバッテリを備えていて、メイン電源に問題がある場合には電力を供給することだ。Googleはまた、2005年以来、同社のデータセンターが標準規格の運送用コンテナで構成されていることを初めて明らかにした。1つのコンテナには1160台のサーバが搭載され、その電力消費は250KWに達する。

Even if you think you’re pretty smart or have a good memory, your brain is begging you to work it to its full potential. Getting stuck in the same routine, never exercising and eating junk food are all brain killers that decrease good cognitive function and increase your chances of memory loss, dementia and Alzheimer’s. But with these 50 tips and ideas for flexing your brain power, you’ll be able to boost performance right now and in the future.

Plugin that monitors the fields you're actually using from queries you make and over time dynamically adjusts your queries to retrieve only the fields you need. Apparently includes some magic to go re-query for more fields if you attempt to use one you hadn't loaded in the trimmed query. Amazing-looking stuff, though since we're currently using a DB on the same machine, transferring lots of extra data isn't nearly as expensive.

Dynamic query optimization is a hotbed of research in the database industry. Each and every query you execute goes through a rigorous optimization phase which tries to squeeze every last bit of performance: deciding which indexes to use, the execution order and sort order to minimize the number in-memory tables, etc. However, one thing the database has no access to is the application layer knowledge of which data the user is actually using after it is retrieved. Often times, the query fetches all of the columns when only a few are required, which is exactly the pattern that Lourens Naudé is seeking to optimize with his new plugin: scrooge.

Dynamic Query Optimization

Excellent description of BASE design patterns

If ACID provides the consistency choice for partitioned databases, then how do you achieve availability instead? One answer is BASE (basically available, soft state, eventually consistent).

Learning jQuery

Including transparent sending of production traffic to staging.

Maybe for Omniture testing?

Lift the curtain behind any modern web application and you will find at least a few proxy servers orchestrating the show. Caching proxies such as Varnish and Squid help us take the load of our application servers; reverse proxies such as Haproxy and Nginx help us partition and distribute the workload to multiple workers, all without revealing the underlying architecture to the user. In the Ruby world, Rack middleware and Rails Metal are sister concepts: both allow the programmer to inject functionality in the pre or post-processing step of the HTTP request.

Three clusters Production (Huge!!) Staging (one) Benchmarking (same as staging)

SQLite Managerを使いプロファイル情報をdb化

this bookmark brought from the different place

In this tutorial, we’ll take a look at the Photoshop Preferences to increase our Performance. With more and more features and important improvements,

Might be a good alternative to Net/HTTP for Context Hero. How hard would it be to incorporate caching?

テストツールのまとめ

(function($) { $.ajax({ url:"/js/file1.js", cache:true, dataType:"text" }); $.ajax({ url:"/js/file2.js", cache:true, dataType:"text" }); })(jQuery);

While users are logging into a web site, I thought why not prefetch some JavaScript files they'll be needing on the next page?

各種ＤＢのサイズ計算方法リンク集

よく使うDB(Oracle/MySQL/PostgreSQL/SQLServer)における設計時のサイズ見積もりで使うサイトの備忘録。

よく使うDB(Oracle/MySQL/PostgreSQL/SQLServer)における設計時のサイズ見積もりで使うサイトの備忘録

Django tip: Caching and two-phased template rendering

It's a clever solution because you end up defining what doesn't get cached instead of what does get cached.

With multi-core processors sitting idle most of the time and workloads always increasing, it's important to have easy ways to make the CPUs earn their money's worth. My colleague Georgios Gousios told me today how the Unix xargs command can help in this regard. The GNU xargs command that comes with Linux and the one distributed with FreeBSD support a -P option through which one can specify the number of jobs to run in parallel. Using this flag (perhaps in conjunction with -n to limit the number of arguments passed to the executing program), makes it easy to fire commands in parallel in a controlled fashion.

The xargs -P flag can also be useful for parellelizing commands that depend on a large number of high-latency systems. Only a week ago I spent hours to write a script that would resolve IP addresses into host names in parallel. (Yes, I know the logresolve.pl that comes with the Apache web server distribution, and the speedup it provides leaves a lot to be desired.) Had I known the -P xargs option, I would have finished my task in minutes.

Multicore-Systeme mit xargs sauber auslasten.

nice summary of different data stores...

TuxRadar

"tagged xorg configuration"

かるくする！

Needle in a haystack: efficient storage of billions of photos

これらを気をつけないと IE では特に遅くなる。jQuery 使う時にはまずはじめに見るべき。

" Using jQuery and other frameworks that make selecting nodes and DOM manipulation easy can have adverse affects if you’re not careful"

Article explaining the basics of how to make a website so it loads efficiently.

mmmmmm

Interesting graphs of languages lining up code size with speed. Use at your own risk.

Planet

一つめのワザは複数枚の画像を1枚にまとめる「CSS Sprite」の採用です。 従来はGIF形式を採用していましたが、これをPNG形式にしました 最後のワザが、PNG形式の制御情報（チャンクと呼ぶ）の削除

チリも積もれば。 ここら辺はYahoo!の素敵なところ。

脱photoshop

たしかに256色減色でPhotoshop使うのはアホだよね。1997年にpag1tetoを使ってた思い出がよみがえった

ヤフーは、あの手この手のワザを駆使して画像ファイルを少しずつ小さくしていったのです。

Page speed is a google tool for evaluating website performance

Page Speed is an open-source Firefox/Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them.

Page Speed is a tool we've been using internally to improve the performance of our web pages -- it's a Firefox Add-on integrated with Firebug.

Website optimization plugin for Firefox/Firebug by Google

チェック！

Web Development Speed Optimization.

Google tips on speeding up the load and render time of a web page.

Check out this SlideShare Presentation : CouchDB: Perform like a pr0n star http://tinyurl.com/cukfou [from http://twitter.com/josefrichter/statuses/1588959474]

"..Page Speed evaluates performance from the client point of view, typically measured as the page load time.."

java applet to check for various nefarious things isps might do, like transparent proxies, dns interception, bittorrent blocking (though not throttling)

The Netalyzr tests your Internet connection for signs of trouble. Understand your connectivity through a detailed report of any performance and security issues.

a basic one about optimizing database query execution time

Indexing the Web

Consejos a través de Twitter

tips on speeding up wp; a little techy for my tastes but useful

In this post we'll explore ten ways to speed up your site, with tricks ranging from easy to even easier; none of the stuff in this post is difficult, so there's no excuse for a slow-loading blog after reading this!

i am guilty of many of these

The first one is to use an in-memory data store, and communicate using the memcached protocol. This is, of course, *exactly* comparable to Memcached — behaviorally indistinguishable! — and it does worse. The second option is to do that, except switch to an on-disk data store. It’s pretty ridiculous that that’s still the same speed — communication overhead is completely dominating the time. Fortunately, Tyrant comes with a binary protocol. Using that substantially improves performance past Memcached levels, though less than a direct in-process database. Yes, communication across processes incurs overhead. No news here, I guess.

"Tokyo Tyrant is a server implemented on top of Cabinet that implements a similar key/value API except over sockets. It’s incredibly flexible; it was very easy to run it in several different configurations. The first one is to use an in-memory data store, and communicate using the memcached protocol. This is, of course, *exactly* comparable to Memcached — behaviorally indistinguishable! — and it does worse. The second option is to do that, except switch to an on-disk data store. It’s pretty ridiculous that that’s still the same speed — communication overhead is completely dominating the time. Fortunately, Tyrant comes with a binary protocol. Using that substantially improves performance past Memcached levels, though less than a direct in-process database. Yes, communication across processes incurs overhead. No news here, I guess."

It's essential that your sites and web apps are constantly accessible to your users. In this article, you will find free and useful monitoring tools to help you know when your website or web application becomes unavailable.

very timely

ind the best way to select elements depending on the situations

celery is a distributed task queue framework for Django. It is used for executing tasks asynchronously, routed to one or more worker servers, running concurrently using multiprocessing.

Not one of those "we're using hadoop, now we're cool" articles. Well written!

Hadoop

Akamaiについて全般的な話。おもしろい。有名どころ・ユーザが多いサービス＝トラフィックが多いってことでよく知られる企業が多く利用しているのね。　細かいことだけど「（インターネットは）冗長性を実現するために信頼性を犠牲にしています。」がちょっと気になった。その後に書いてある速度の話は信頼性に分類されるのかな。

みんなが知らずに使ってるAkamai

If you are Digg or LinkedIn you can build your own speedy graph database to represent your complex social network relationships. For those of more modest means Neo4j, a graph database, is a good alternative. A graph is a collection nodes (things) and edges (relationships) that connect pairs of nodes. Slap properties (key-value pairs) on nodes and relationships and you have a surprisingly powerful way to represent most anything you can think of. In a graph database "relationships are first-class citizens. They connect two nodes and both nodes and relationships can hold an arbitrary amount of key-value pairs. So you can look at a graph database as a key-value store, with full support for relationships."

another graphbase

JavaScriptDB: Persevere’s New High-Performance Storage Engine April 20th, 2009 at 8:47 pm by Kris Zyp The latest beta of Persevere features a new native object storage engine called JavaScriptDB that provides high-end scalability and performance. Persevere now outperforms the common PHP and MySQL combination for accessing data via HTTP by about 40% and outperforms CouchDB by 249%. The new storage engine is designed and optimized specifically for persisting JavaScript and JSON data with dynamic object structures. It is also built for extreme scalability, with support for up to 9,000 petabytes of JSON/JS data in addition to any binary data.

Having a blog that’s snappy &amp; responsive is just one of the many factors that makes a great blog. Even with the best content in the world, a slow blog will frustrate readers &amp; potentially force them elsewhere. In this post we’ll focus on optimising Wordpress, a popular free open source blogging platform that runs on PHP.

Guia de optimizacion de WordPress 2.8

Having a blog that’s snappy & responsive is just one of the many factors that makes a great blog. Even with the best content in the world, a slow blog will frustrate readers & potentially force them elsewhere. In this post we’ll focus on optimising Wordpress, a popular free open source blogging platform that runs on PHP.

Page Speed is an open-source Firefox/Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them. How does Page Speed work? Page Speed performs several tests on a site's web server configuration and front-end code. These tests are based on a set of best practices known to enhance web page performance. Webmasters who run Page Speed on their pages get a set of scores for each page, as well as helpful suggestions on how to improve its performance. Why should you use Page Speed? By using Page Speed, you can: * Make your site faster. * Keep Internet users engaged with your site.

Page Speed is an open-source Firefox/Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them.

A plugin for Firebug similar to YSlow

What is Page Speed? Page Speed is an open-source Firefox/Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them.

cal production Rails app on Ruby 1.8 can recover 20% to 40% o

his article will present ten easy steps that will instantly improve your script's performance. Don't worry; there isn't anything too difficult here. Everyone can apply these methods! When you're finished reading, please let us know your speed tips.

SpriteMe makes spriting easy.

export the modified CSS to integrate back into your code. [TBD]

SpriteMe

Don't know when I'll ever get round to reading this!

Discover best practices that can make your apps faster. Get informed with developments in web performance.

Agilidade na web

Google resource center on performance optimization. Articles, videos and downloadable tools. Includes tips on how to optimize CSS declarations, how to optimize JavaScript code and avoid memory leaks, how to use the best image format and prefetch resources. Also released Google equivalent of YSlow, Yahoo's Firefox extension for performance tips.

recently started using chrome, hmmm

Google Chrome

Milyen az új Chrome?

Problem. You are interested in how the Google Chrome 3.0 Dev, Firefox 3.5 RC, Safari 4.0 for Windows, and Opera 10b web browsers manage memory on the Windows Vista operating system over moderate usage, such as with 150 top web sites. These numbers can be measured but there are complexities involved in measuring memory. Solution. Here we look at a program that simulates a user visiting the top 150 web sites from Alexa from the command line, with visits occurring at short but varying intervals in many tabs.

So firefox is the best. Premature optimisation anyone?

Page Speed

Google code - Page Speed

One MILLION connections !

Cuzillion

Paperclip

20 Linux System Monitoring Tools Every SysAdmin Should Know

MySpace’s Performance Tracker is a browser plugin that help developers to improve their code performance by capturing and measuring possible bottlenecks on their web pages. MySpace’s Performance Tracker Features * Measure the CPU hit and memory footprint of your pages as they render on the client’s browser * Review screen shots of the page while it renders * Review the rendered HTML on each point of the page’s lifecycle * Measure and show estimates of the time it takes to render each section of the page in different connection speeds * Validate the content of your page against a set of proven “best practice” rules of web development * Review downloaded files and show download time estimation on different bandwidths MySpace’s Performance Tracker currently supports Internet Explorer 6 and up.

IEプラグイン、←YSlow/Google Page Speed、パフォーマンス/高速化/レンダリング

MySpace’s Performance Tracker MySpace’s Performance Tracker is a browser plugin that help developers to improve their code performance by capturing and measuring possible bottlenecks on their web pages. MySpace’s Performance Tracker Features * Measure the CPU hit and memory footprint of your pages as they render on the client’s browser * Review screen shots of the page while it renders * Review the rendered HTML on each point of the page’s lifecycle * Measure and show estimates of the time it takes to render each section of the page in different connection speeds * Validate the content of your page against a set of proven “best practice” rules of web development * Review downloaded files and show download time estimation on different bandwidths MySpace’s Performance Tracker currently supports Internet Explorer 6 and up.

Cause memory leaks love IE?....

Example of ActionScript profiler to track framerate or memory usage

This handy script applies a profiler option to the right click Flash Context Menu which allows you to debug or track the current FPS or memory used by your SWF. Further to this it also stores a configurable history length of the frame rate and memory performance for the SWF.

SWF Profiler

Flash の メモリ使用量やフレームレートなどのパフォーマンスが分かるライブラリ。

クラウドコンピューティングの問題点の一つに、レイテンシ（通信遅延）の問題があると言われます。これは光ファイバを通じる光の伝搬速度は一定なので、距離が遠ければ遠いほど遅くなり、海の向こうのサーバがある以上は、SSHでのターミナル画面の文字入力は相応に遅延します。

Firefox 3では、履歴やブックマーク、クッキーなどの他、一部アドオンの利用データもSQLite データベースで管理しています。 日々の利用により、このデータベースが大きくなってくると、Firefoxの起動に時間がかかったり、動作が緩慢になってくるということなどが考えられます。 このようなとき、データベースの最適化をすることによって、Firefoxの動作を軽くするという方法がブログなどにもよく書かれていますが、これを実行するには「SQLite Manager」というアドオンをFirefoxにインストールして起動し、お使いのプロファイルフォルダから該当データベースを探して[Reindex]を行うという作業が必要となり、初心者にはちょっと実行しにくいものがあります。

実験的アドオンが終了次第導入。

a first step to investigate search engine.

Later this month we will be presenting a half day tutorial on Open Search at SIGIR. It’ll basically focus on how to use open source software and cloud services for building and quickly prototyping advanced search applications. Open Search isn’t just about building a Google-like search box on a free technology stack, but encouraging the community to extend and embrace search technology to improve the relevance of any application.

visto en el twitter de torresburriel

How To Increase Site Performance Through A/B Split Testing

Once upon a time, all we needed to worry about was reducing Bytes and Requests and playing around with load order to make things faster. Nowadays, we are

If you really want to fine-tune your Firefox functionality, you have to roll up your sleeves and tinker with the about:config page. Jack Wallen shares some simple hacks to make Firefox work the way you want.

A team member thought we should add an index on a 90 million row table to improve performance. The field on which he wanted to create this index had only four possible values. To which I replied that an index on a low cardinality field wasn't really going to help anything. My boss then asked me why wouldn't it help? I sputtered around for a response but ended up telling him that I'd get back to him with a reasonable explanation.

Imported from http://twitter.com/newsycombinator/status/2645303258 How b-tree database indexes work and how to tell if they are efficient http://bit.ly/dd6mf

Stack Overflow Architecture | High Scalability

Stack Overflow is a much loved programmer question and answer site written by two guys nobody has ever heard of before. Well, not exactly. The site was created by top programmer and blog stars Jeff Atwood and Joel Spolsky. In that sense Stack Overflow is like a celebrity owned restaurant, only it should be around for a while. Joel estimates 1/3 of all the programmers in the world have used the site so they must be serving up something good.

Vergleich verschiedener JPAs

In looking at your code, none of your queries actually return an objects. They are all count queries, returning a single number. Hardly a typical usage of object-relational mappings, makes the comparison not very useful.

398

Case study on Redis

Just wanted to add that even though there is a single point of failure the reliability due to software bugs has not been an issue and the dfs Namenode has been very stable. The Jobtracker crashes that we have seen are due to errant jobs - job isolation is not yet that great in hadoop and a bad query from a user can bring down the tracker (though the recovery time for the tracker is literally a few minutes). There is some good work happening in the community though to address those issues.

I few weeks ago, I posted about a conversation I had with Jeff Hammerbacher of Cloudera, in which he discussed a Hadoop-based effort at Facebook he previously directed. Subsequently, Ashish Thusoo and Joydeep Sarma of Facebook contacted me to expand upon and in a couple of instances correct what Jeff had said. They also filled me in on Hive, a data-manipulation add-on to Hadoop that they developed and subsequently open-sourced.

How To Automate Optimization and Deployment Of Static Content

This application is aimed to automate all clientside improvements for website that should significantly increase load speed of its pages.

"A 'worker' is a script that will be loaded and executed in the background. Web Workers provide a way to do this seamlessly, for example: new Worker("worker.js") - available in Firefox, Safari and Chrome - "If you're doing any computation with JavaScript you should definitely opt to use Web Workers if they're available"

Computing with JavaScript Web Workers

"Normally in order to achieve any sort of computation using JavaScript you would need to break your jobs up into tiny chunks and split their execution apart using timers. This is both slow and unimpressive ..."

my students Azza Abouzeid and Kamil Bajda-Pawlikowski developed HadoopDB. It's an open source stack that includes PostgreSQL, Hadoop, and Hive, along with some glue between PostgreSQL and Hadoop, a catalog, a data loader, and an interface that accepts queries in MapReduce or SQL and generates query plans that are processed partly in Hadoop and partly in different PostgreSQL instances spread across many nodes in a shared-nothing cluster of machines. In essence it is a hybrid of MapReduce and parallel DBMS technologies. But unlike Aster Data, Greenplum, Pig, and Hive, it is not a hybrid simply at the language/interface level. It is a hybrid at a deeper, systems implementation level. Also unlike Aster Data and Greenplum, it is free and open source.

Velocity Conference.

Stats on how much users choose to leave a page as load time increases

Awesome study -- everyone knows speed is "good," but this quantifies it.

Not too long ago, I wrote about loading JavaScript without blocking by creating a dynamic <script> tag. When <script> tags are in the flow of an HTML document, the browser must stop rendering and wait for the script file to download and execute before continuing (example). Creating a new <script> tag via JavaScript avoids this issue because it’s out of the flow of the document, so the script file is downloaded and executed without waiting. The result: dynamically loading JavaScript files allows your page to render faster and therefore improve perceived performance.

handling dependancies in js

重いFirefoxをなんとかして速くしたい

モバゲーのインフラの話

1日6億PVを6人のインフラ担当で支えられる理由

MySQL is a widely used and fast SQL database server. It is a client/server implementation that consists of a server daemon (mysqld) and many different client programs/libraries. Here are very useful tips for all mysql DBA’s, Developers these tips are noted from MySQL Camp 2006 suggested by mysql community experts.

# # Don’t use DISTINCT when you have or could use GROUP BY

Don’t use deprecated features

Intéressant, une étude des différentes db alternatives sous l'angle de la scalabilité

http://aws.amazon.com/s3/

data store scaling technologies

a thin wrapper around Rack middleware intended for application-specific end points that need the extra speed

Annotated link http://www.diigo.com/bookmark/http%3A%2F%2Fhacks.mozilla.org%2F2009%2F07%2Ftracemonkey-overview

This will explain what kinds of programs get the best speedup from TraceMonkey and what kinds of things you can do to get your program to run faster.

The Adobe AIR platform makes it possible for many talented developers familiar with AJAX or Flash to build desktop applications. However, with great power comes great responsibility.

Siinä testiä

# Reverse Worker Code $worker= new GearmanWorker(); $worker->addServer(); $worker->addFunction("reverse", "my_reverse_function"); while ($worker->work()); function my_reverse_function($job) { return strrev($job->workload()); }

Gearman provides a generic application framework to farm out work to other machines or processes that are better suited to do the work. It allows you to do work in parallel, to load balance processing, and to call functions between languages. It can be used in a variety of applications, from high-availability web sites to the transport of database replication events. In other words, it is the nervous system for how distributed processing communicates.

language independent worker framework

In the last post I wrote on caching in Hibernate in general as well as on the behavior of the session cache. In this post we will have a closer look at the QueryCache. I will not explain the query cache in details as there are very good articles like Hibernate: Truly Understanding the Second-Level and Query Caches.

To keep the Google Analytics code from interfering with page rendering you can use jQuery to load and execute the ga.js file. The ‘jquery.geekga.js

Speeding up Google Analytics

50 expert tips to make your PC faster Speed up your PC without paying for upgrades : TechRadar UK

While CSS sprites offer nice performance benefits (less connections/overhead), they are troublesome in every respect. Putting lots of tiny images with different dimensions into one bigger image is fiddly and very hard – np-hard in fact. But that's the smallest issue. It doesn't need to be perfect after all. Deflate will happily squish all that extraneous white-space to virtually nothing. One of the real problems is CSS. It just isn't flexible enough to let you do everything you might want to do with your sprite sheet. For example repeating parts of the image isn't possible. And if you want to display a sub region of an image in the upper right of some element, it only works if that sub region is in the lower left of the sprite sheet. So, the best thing you can do is to use elements in the size of the sub region and use background-position to slide the image around, but that usually means extra markup for something that should be very simple.

One aspect of web development that is many times overlooked is search engine optimization. In this list, I’ll show you some basic SEO techniques that will help you make friends with Google, and increase your page rank!

Here is a collection of some testing tools that we have compiled to aid your testing handily grouped into categories. Look out for our reviews of some of these tools coming soon.

Testing Web Sites

Just about everyone wants to do great work, look good in the eyes of their boss, and earn the respect of their peers.

Más práticas de Javascript

Looks very similar to Steve Souders' YSlow extension.

Google __Page Speed__ sounds like Yahoo's Y Slow.

Components.classes["@mozilla.org/browser/nav-history-service;1"].getService(Components.interfaces.nsPIPlacesDatabase).DBConnection.executeSimpleSQL("VACUUM");

Both useful and pretty. There are precisely 2 good Photoshop performance tips here, but the real draw is Dan Rubin's luscious CSS3-implemented design.

By http://bit.ly/Tweets2Delicious

Optimization of website performance.

A common complaint about mod_python is that it uses too much memory and can cause huge spikes in processor load. Fact is that this isn't really caused by mod_python itself, but indirectly by virtue of how, or more so how not, Apache has been configured for the type of web application that is being run.

this is IMPORTANT

Some have realised that mod_wsgi daemon mode seems to offer a more predictable memory usage profile and performance curve and as a result fervently recommend it, but at the same time they still don't seem to understand what the problems with embedded mode, as outlined above actually were. So, hopefully the explanation above will help in clearing up why, not just in the case of mod_wsgi daemon mode vs mod_wsgi embedded mode, but also for the much maligned mod_python.

out of date, hence the mod_python, but the apache conf still applies

Make your pages load faster by combining and compressing javascript and css files | rakaz

This post is based on a chapter from Even Faster Web Sites, the follow-up to High Performance Web Sites. Posts in this series include: chapters and contributing authors, Splitting the Initial Payload, Loading Scripts Without Blocking, Coupling Asynchronous Scripts, Positioning Inline Scripts, Sharding Dominant Domains, Flushing the Document Early, Using Iframes Sparingly, and Simplifying CSS Selectors. “Simplifying CSS Selectors” is the last chapter in my next book. My investigation into CSS selector performance is therefore fairly recent. A few months ago, I wrote a blog post about the Performance Impact of CSS Selectors. It talks about the different types of CSS selectors, which ones are hypothesized to be the most painful, and how the impact of selector matching might be overestimated. It concludes with this hypothesis:

[Browsers read CSS selectors from right to left, therefore...] The key to optimizing CSS selectors is to focus on the rightmost selector, also called the key selector (coincidence?). Here’s a much more expensive selector: A.class0007 * {}. Although this selector might look simpler, it’s more expensive for the browser to match. Because the browser moves right to left, it starts by checking all the elements that match the key selector, “*“. This means the browser must try to match this selector against all elements in the page.

speed up

Vacuum Firefox databases for better performance, now with no restart

Components.classes["@mozilla.org/browser/nav-history-service;1"].getService(Components.interfaces.nsPIPlacesDatabase).DBConnection.executeSimpleSQL("VACUUM");

MySQLで索引を使っていないクエリーをログを調べずに見つける方法

"WSGI middleware which displays sparklines of Python object counts and allows you to introspect them, using the gc module under the hood"

Finding and fixing memory leaks can be a real challenge, but luckily Python has some pretty good tools for spotting these things. I have already written about this issue and this post will go into more details on how to spot and debug a memory leak in MySQLdb, which is the standard Python wrapper for MySQL.

18 Useful Tricks To Speed Up WordPress & Boost Performance - http://www.wpbeginner.com/wp-tutorials/18-useful-tricks-to-speed-up-wordpress-boost-performance/

6. Optimize Your MySQL Database Optimizing your MySQL Database can make a difference in your load time. There are two ways of doing this. One way is manual hard core way. Another way is a plugin. To do it manually, you need to go to phpMyAdmin and select your database. Then towards the bottom, click check all to select all tables and then towards the center of the screen, there is a drop down menu, click optimize tables there. Optimize MySQL Database

<?php echo get_num_queries(); ?> queries in <?php timer_stop(1); ?> seconds.

FreightRefunds.com - Provides freight audit for clients who ship cargo via ocean freight and the refunds are paid to clients directly from the service providers.If your company is not paid a refund, our service at Ocean Freight Refunds Inc. (OFR) is free of charge.

お役立ち

環境設定でメモリ使用状況を最小限にする方法

photoshop高速化

ou combined memory

"...what effect does the large-scale structure of the JS output code have on the DEFLATE algorithm of GZIP which is used to serve up compressed script?" Another instance of using knowledge of the specific file type to get gains in compression. Is there a web proxy running all this at which I can point my phone?

On JavaScript minification and compression.

better compression through instruction rearrangement. this guy drives me somewhat crazy, but he does cool work.

Cliff Click Jr.’s Blog

I just foolishly got caught in a You-Tube discussion on Java vs C performance. Foolish because You-Tube comments are a lousy way to present anything and because it's hard to keep the level of discourse scholarly. And foolish especially for me because I've had this discussion so many times and it always comes out the same way... so here's my attempt at distilling my arguments into something I can point people the *next* time I get caught in this silly discussion. Is Java faster than C/C++? The short answer is: it depends.

Let's make the web faster

Javascriptの読込みは</body>のすぐ前が良いって聞いたことがある。

4 Cool Firefox Tools That Are Not Addons

answer is 3TB database???

"The fundamental problem is endemic to the relational database mindset, which places the burden of computation on reads rather than writes."

Wow, cassandra uses a lot of disk space. Trade offs!

"open source version of the scalable, non-blocking web server and and tools that power FriendFeed"

Tornado is an open source version of the scalable, non-blocking web server and tools that power FriendFeed. The FriendFeed application is written using a web framework that looks a bit like web.py or Google's webapp, but with additional tools and optimizations to take advantage of the underlying non-blocking infrastructure.

Tornado is an open source version of the scalable, non-blocking web server and tools that power FriendFeed.

As a Web developer it's always a good idea to know what the current practices are in the industry even if they seem a bit too crazy to adopt…yet.

bit on why non-SQL dbs are used in social networking sites

Common causes of memory related issues - out of memory, excessive memory usage, and memory leaks in java applications.

Memory Leaks and other memory related problems are among the most prominent performance and scalability problems in Java. Reason enough to discuss this topic in more detail.

.

) doesn’t know how to use raw flash. So if you want a few 80 gigabytes of flash in a laptop, today the only way to get it is with it attached to a SATA interface in a 2.5″ laptop disk form

Formatowanie SSD

js-powered css, acid3, etc. browser tests and results

Recent tests 12:13 p.m. Other acid3 100 12:13 p.m. Firefox 3.5 richtext 117/149 12:13 p.m. Firefox 3.5 selectors 99.3% 12:13 p.m. Firefox 3.5 acid3 93 12:13 p.m. Chrome 4.0.206 network 9/11 12:13 p.m. Firefox 3.5 network 9/11 12:12 p.m. Konqueror 4.3 richtext 0/149 12:12 p.m. Konqueror 4.3 selectors 0% 12:12 p.m. Firefox 3.0.14 richtext 117/149 12:11 p.m. Konqueror 4.3 acid3 89 Browserscope is a community-driven project for profiling web browsers. The goals are to foster innovation by tracking browser functionality and to be a resource for web developers. Gathering test results from users "in the wild" is the most important and useful feature of Browserscope - and you can participate!

Browserscope is a community-driven project for profiling web browsers. The goals are to foster innovation by tracking browser functionality and to be a resource for web developers.

Background images make pages look good, but also make them slower. Each background image is an extra HTTP request. There's a fix: combine background images into a CSS sprite. But creating sprites is hard, requiring arcane knowledge and lots of trial and error. SpriteMe removes the hassles with the click of a button.

Loads javascript in parts - gains up to 40% in page load speed (nice to have)

An AJAX application optimization tool from Microsoft.

Doloto is an AJAX application optimization tool, especially useful for large and complex Web 2.0 applications that contain a lot of code, such as Bing Maps, Hotmail, etc. Doloto analyzes AJAX application workloads and automatically performs code splitting of existing large Web 2.0 applications. After being processed by Doloto, an application will initially transfer only the portion of code necessary for application initialization.

Using Page Speed

"Page Speed is an open-source Firefox/Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them."

ools > Firebug > Open Firebug

photoshop performance

And another...a bit more technical.

This is amazing - MS is providing a Content-Distrib-Network for us to use for free, to distribute the jQuery and ASP.NET-AJAX files.

Bookmarklet, das die Stylesheets und Hintergrundbilder einer Seite auswertet und Bilder vorschlägt, die man in Sprites vereinigen kann. Per Knopfdruck wird entsprechende Sprite generiert.

Sprite your icons and small images to minimize the number of HTTP requests you make.

Includes links on initiatives, techniques, and development (opening up by the FCC of the white spectrum) that can make the web faster

Very interesting possibilities with this HTML5 feature. I'm intrigued to see the capabilities it can show in future web apps - if it lives up to expectations.

Mejorar la velocidad de JSON

When you’re working with JSON, performance and security are often opposing, yet equally important concerns. One of these areas of contention is handling the JSON strings returned by a server. Most JavaScript libraries do a great job of abstracting away the details, but the underlying process has long been a frustrating exercise in compromise. On one hand, eval() is the fastest widely available method, but it is not safe. On the other hand, textual JSON parsers written in JavaScript may be much safer, but are dramatically slower. In client-side situations, where milliseconds count, such a large performance overhead is typically too prohibitive to accept. Recently, an exciting new alternative has emerged: browser-native JSON parsing. Integrating JSON parsing as part of the browser’s implementation of JavaScript allows for using the more secure parsing method, and even provides performance faster than eval() offers.

Recently, an exciting new alternative has emerged: browser-native JSON parsing. Integrating JSON parsing as part of the browser’s implementation of JavaScript allows for using the more secure parsing method, and even provides performance faster than eval() offers. To take advantage of that, this post will show you how to detect whether or not a browser supports native JSON parsing, and how to force jQuery to use browser-native parsing in its $.ajax calls when it is available.

Need to check this out

Google Apps Status Dashboard enables users and businesses to monitor the status of individual Google Apps services. Users of Google Apps can now view the status of individual services such as Gmail/Google Mail, Google Calendar, Google Talk, Google Docs, Google Sites and Google Video for businesses. Administrators of Google Apps Premier Edition, Standard Edition, Partner and Education Edition can also view status of the Admin Control Panel.

How Ravelry Scales to 10 Million Requests Using Rails

Interessantissimo articolo su un sito web fatto in rails (www.ravelry.com) che ha raggiunto volumi di traffico davvero ragguardevoli. L'articolo illustra come è nata l'idea per il sito (si tratta di un sito per gli appassionati di cucito e lavoro a maglia), come si è arrivati a quei numeri (10 million requests a day hit Rails, 3.6 million pageviews per day, 430,000 registered users. 70,000 active each day. 900 new sign ups per day), dell'architettura adottata, e delle lezioni imparate.

Tim Bray has a wonderful interview with Casey Forbes, creator of Ravelry, a Ruby on Rails site supporting a 400,000+ strong community of dedicated knitters and crocheters.

Optimize and monitor your Wordpress blog is necessary so that you can reduce the load time, bandwidth and server usage. This article discuss 15 tips and plugins to preform Wordpress web optimization.

unnecessary plugins can also remove the unwanted hooks. Hooks are provided by Wordpress to allow the plugi

An AWESOME reference on bandwidth for engineers.

This is a unique YDN blog post.

scalablity

サブクエリ、あんまりよくない理由

というわけでMySQLによるサブクエリの処理について見てきたが、きちんと気をつけて使えばサブクエリも高速に実行される。もちろんJOINに書き換えた方が速いのは言うまでもないが、SQL文のメンテナンスし易さなどを考えるとサブクエリで処理を書きたい！という人も居るのではないだろうか。そんな方は次の事に気をつけてサブクエリを使って頂きたい。 * サブクエリの種類 * 外部クエリとサブクエリの評価の順序 * 外部クエリにおいてフェッチされる行数 * サブクエリで利用されるインデックス * テンポラリテーブルのサイズ

Top 5 Vista Tweaks to Increase Internet Speed

Earlier this week, 1.5 million people filled the streets of Berlin, Germany to watch a several-day performance by France's Royal de Luxe street theatre company titled "The Berlin Reunion". Part of the celebrations of the 20th anniversary of the fall of the Berlin Wall, the Reunion show featured two massive marionettes, the Big Giant, a deep-sea diver, and his niece, the Little Giantess.

giant marionettes

This is amazing.

The Big Picture - News Stories in Photographs from the Boston Globe

「content.notify.backoffcount」を整数で新規作成して「5」を設定、「nglayout.initialpaint.delay」を整数で新規作成して「0」を設定

キャッシュやクッキー、履歴データなどの削除することは起動や操作が高速になる半面、レンダリングや利用の面で不便になることに注意する必要. 「content.notify.backoffcount」を整数で新規作成して「5」を設定、「nglayout.initialpaint.delay」を整数で新規作成して「0」を設定する。最初の設定はすべてのページをダウンロードし終わる前にレンダリングを開始する指定、後者はページレイアウト情報をすべてダウンロードする前にレンダリングを開始する指定... メニューを高速化する 「ui.submenuDelay」を整数で新規作成して「0」を設定... IPv6対応機能を無効にする IPv6を使う必要がなければ「network.dns.disableIPv6」の値を「true」に変更...

javascript.options.jit.content

ui.submenuDelay

Unicorn is an HTTP server for Ruby, similar to Mongrel or Thin. It uses Mongrel’s Ragel HTTP parser but has a dramatically different architecture and philosophy.

A user named Apathy in this thread on how Reddit scales some of their features, shares some advice he learned while working at Google and other major companies. To be fair, I [Apathy] was working at Google at the time, and every job I held between 1995 and 2005 involved at least one of the largest websites on the planet. I didn't come up with any of these ideas, just watched other smart people I worked with who knew what they were doing and found (or wrote) tools that did the same things. But the theme is always the same: # Cache everything you can and store the rest in some sort of database (not necessarily relational and not necessarily centralized). How do you go about applying this strategy?

ing caches is a clasisc strategy for milking your servers as much as possilbe. First look for an exact match. If that's not foun

Here’s a dozen tips for working with a PostgreSQL database. It is a sophisticated and powerful piece of software and just knowing a few rules of thumb before diving in can be a huge help.

Here’s a dozen tips for working with a PostgreSQL database. It is a sophisticated and powerful piece of software and just knowing a few rules of thumb before diving in can be a huge help. If you want more detail read the amazing documention. My list of tips was very long so I just chopped off a dozen for this post.

Cogent

I started doing some research to answer these questions, but during that time there have been a number of great posts about @font-face performance issues: * Paul Irish: Fighting the @font-face FOUT * Stoyan Stefanov: Gzip your @font-face files * Zoltan Hawryluk (again): More @font-face fun This blog post summarizes Paul, Stoyan, and Zoltan’s findings plus some very important discoveries of my own.

Lazy load to the resuce then…

Last week I was reading Ajaxian (my favorite blog) and saw the post about @font-face. I had been wondering for a few months about how font files impact web performance, so I followed the story back to Zoltan Hawryluk’s original post: @font-face in Depth. A great read on the aesthetics, mechanics, and compatibility issues of fonts, but not much about performance. I added a comment:

In this tutorial I'll show you how to setup and use Amazon's Web Services S3 and CloudFront to decrease website load time as well as show the performance differences.

ブラウザ、パフォーマンス、グラフ/比較

The latest versions of the five major most web browsers (Firefox 3.5, Chrome 3.0, IE8, Opera 10, and Safari 4) went head to head under six performance indicators: JavaScript speed, average CPU usage under stress, DOM selection, CSS rendering speed, page load time, and browser cache performance.

The latest versions of the five major most web browsers (Mozilla Firefox 3.5, Google Chrome 3.0, Microsoft Internet Explorer 8.0, Opera 10.0, and Apple Safari 4.0) went head to head under six performance indicators: JavaScript speed, average CPU usage under stress, DOM selection, CSS rendering speed, page load time, and browser cache performance. Each web browser was tested three times under an unprimed cache (except for the browser cache performance), and their average value reported in the results.

とても勉強になる。

W3 Total Cache

Another amazing post about WordPress Plugins. Can't get enough of testing out new plugins.

A software-based distributed caching system such as memcached is an important piece of today's largest Internet sites that support millions of concurrent users and deliver user-friendly response times. The distributed nature of memcached design transforms 1000s of servers into one large caching pool with gigabytes of memory per node. This blog entry explores single-instance memcached scalability for a few usage patterns.

"A software-based distributed caching system such as memcached is an important piece of today's largest Internet sites that support millions of concurrent users and deliver user-friendly response times. The distributed nature of memcached design transforms 1000s of servers into one large caching pool with gigabytes of memory per node. This blog entry explores single-instance memcached scalability for a few usage patterns."

Grant SkinnerさんによるAS3のパフォーマンステスト用クラス。

パフォーマンステスト用ライブラリ、負荷かかる処理やコードの最適化に使えそう。 チュートリアルhttp://gotoandlearn.com/play?id=115

more

gskinnerさま

Here's a simple demo of it in action.

MySQLのInnnoDB、MyISAMの利点・欠点がまとめられている。参考になります。

自分は、特別な事情が無い限り、5.1最新版に含まれるInnoDB Pluginを勧めています。

Since 2005, VMware and Xen have gradually reduced the performance overheads of virtualization, aided by the Moore’s law doubling in transistor count, which inexorably shrinks overheads over time. AMD’s Rapid Virtualization Indexing (RVI – 2007) and Intel’s Extended Page Tables (EPT – 2009) substantially improved performance for a class of recalcitrant workloads by offloading the mapping of machine-level pages to Guest OS “physical” memory pages, from software to silicon. In the case of operations that stress the MMU—like an Apache compile with lots of short lived processes and intensive memory access—performance doubled with RVI/EPT. (Xen showed similar challenges prior to RVI/EPT on compilation benchmarks.)

300000

YouTubeなどの動画サイトで10秒ごとに動画がフリーズするのは、Firefox2.0以降に搭載されているセッション復元機能が原因だとか。Firefoxのデフォルト値では開いているタブを10秒ごとに保存する設定になっているそうで、多くのタブを一度に開いているとより動画が固まりやすいそうです。 では、これを解消するためにはどうすればよいのでしょう？ 答えはシンプル。セッション復元のための保存のインターバルを長くすること。具体的な方法としては、アドレスバーで「about:config」と入力しEnterキーを押すと、フィルターボックスが表示されますので、さらにフィルターボックスに「browser.sessionstore.interval」と入力しましょう。すると「10000（"10秒に保存する"の意）」が表示されるはず。この数値を5分ごとの保存とするならば「300000」、2分なら「120000」など、任意の数字に変更すればOK。

セッション保存のインターバルを長くする方法 / browser.sessionstore.interval = 120000 (=2分) など

The aim of this project is to create an ideal administration tool which can prevent running any application in Windows. The development process is divided into a series of stages, each of them being indicated in the roadmap section. The project is targeted at the corporate audience and, among other things, sets a goal to develop powerful features for remote administration of all domain computers at once. The project started on October 20, 2008.

I Will Teach You How To Be Rich

Sun now integrates a profiler in the jdk

Java VisualVM – Developer`s Nightmare is Over

VisualVM is an open source tool for monitoring and profiling your Java applications. VisualVM is now integrated with JDK 6 update 7 release and also available as a stand-alone setup. Java 7 plans to integrate next version 1.2.

technical ramblings from a wanna-be unix dinosaur

We are using Wordpress as CMS for this blog, hence we decided to install WP-Super cache plugin for Wordpress to improve the performance. This plugin will create static HTML files from your blogs post and other pages and save them on web server. These HTMLs are served to client whenever consecutive requests are made. Hence this greatly improve the performance as it reduce PHP parsing and database connections. Bandwidth control is an important task to be followed when your traffic is increasing. With limited monthly bandwidth hosting, your site may run out of bandwidth and thus result in increase in down time. Hence it is very much advisable to compress your websites response with GZip and then serve it to client. Compressing output can significantly improve your websites performance by reducing the size sometimes upto 80%

This tool lets you test web pages that are directly accessible as an URL from the Internet.

Welcome. Pagetest allows you to provide the URL of a webpage to be tested. The test will be conducted from the location specified and you will be provided a waterfall of your page load performance as well as a comparison against an optimization checklist. Please visit the PageTest wiki page for more information. Sample results for AOL.com can be seen here.

"Closure Compiler is a JavaScript optimizer that compiles web apps down into compact, high-performance JavaScript code. The compiler removes dead code, then rewrites and minimizes what's left so that it will run fast on browsers' JavaScript engines. The compiler also checks syntax, variable references, and types, and warns about other common JavaScript pitfalls. These checks and optimizations help you write apps that are less buggy and easier to maintain. You can use the compiler with Closure Inspector, a Firebug extension that makes debugging the obfuscated code almost as easy as debugging the human-readable source. "

As we continue exploring our mistakes, with last week’s blog challenge about the worst mistake we’ve made in a relationship, this week I’m going to challenge your work history and experience.

"The Closure Compiler is a tool for making JavaScript download and run faster. It is a true compiler for JavaScript. Instead of compiling from a source language to machine code, it compiles from JavaScript to better JavaScript. It parses your JavaScript, analyzes it, removes dead code and rewrites and minimizes what's left. It also checks syntax, variable references, and types, and warns about common JavaScript pitfalls. Efficiency. The Closure Compiler reduces the size of your JavaScript files and makes them more efficient, helping your application to load faster and reducing your bandwidth needs. Code checking. The Closure Compiler provides warnings for illegal JavaScript and warnings for potentially dangerous operations, helping you to produce JavaScript that is less buggy and and easier to maintain."

is a tool for making JavaScript download and run faster. It is a true compiler for JavaScript.

Compressore Javascript Google

Google JavaScript Compiler

This strategy is stated perfectly by Flickr's Myles Grant: The Flickr engineering team is obsessed with making pages load as quickly as possible. To that end, we’re refactoring large amounts of our code to do only the essential work up front, and rely on our queuing system to do the rest. Flickr uses a queuing system to process 11 million tasks a day. Leslie Michael Orchard also does a great job explaining the queuing meme in his excellent post Queue everything and delight everyone. Asynchronous work queues are how you scalably solve problems that are too big to handle in real-time.

[vía @basilio] # Learn the difference between good and bad code. read more # Stick to coding standards, it will make it easier for you to understand other people’s code and other people will be able to understand yours. read more

PHP programming tips and tricks

"Sharding kills most of the value of a relational database."

sql database db

innodbの書き込み速度を上げるtipsと、その他設定について

sudo hdparm -W 0 /dev/sda

Rainmeter is a desktop customization platform. Through Rainmeter, you can enhance your Windows computer at home or work with skins: handy, compact applets which float freely on your desktop, much like Windows Sidebar gagdgets, or dashboard widgets for the Mac. Rainmeter skins provide you with useful information at a glance. It's easy to keep an eye on your system resources, like memory and battery power, or your online data streams, including email, RSS feeds, and weather forecasts. Many skins are even functional: they can record your notes and to-do lists, launch your favorite applications, and send your tweets to Twitter - all in a clean, unobtrusive interface that you can rearrange and customize to your liking.

Rainmeter is a desktop customization platform. Through Rainmeter, you can enhance your Windows computer at home or work with skins: handy, compact applets which float freely on your desktop, much like Windows Sidebar gagdgets, or dashboard widgets for the Mac.

customizable resource meter

personalized desktop

desktop totalmente irado

What if Google released a JavaScript library that sucked, and no one noticed? JavaScript expert Dmitry Baranovskiy has peeked under the hood of Google’s new Closure Library, and he doesn’t like what he sees. Follow along as he points out a few of the library’s many failings, and why the Web deserves better from Google.

@kasthomas: "SPDY, Google's answer to HTTP http://3.ly/Qbp" (from http://twitter.com/kasthomas/status/5693351096)

Is real-time query performance and diagnostics tool for the MySQL database server.

Java desktop graphical MySQLprofiler. Free version.

Real-time query performance and diagnostics tool for the MySQL database server.

4 tips buenos para mejorar el desempeño de MySQL.

MySQL configuration variables that have defaults which have proven to be problematic in a high-volume production environment

You know CSS, but do you know how to optimize it? I have gathered a list of CSS optimization and CSS File size reduction tips and tricks that will help you writing a more effective and efficient CSS code.

Tornado: Facebook's Real-Time Web Framework for Python

Possible to build a site like FB.. using Tornado Cassandra, Hive (hadoop underneath) memcache, Scribe, Thrift.

Real-time updates have become an important aspect of the social Web that make it easier to share with friends. In March, we introduced a real-time News Feed to make the stream as relevant and engaging as possible for users. Similarly, FriendFeed, which we recently acquired, built their entire site to support real-time updates. It hasn't been easy to build and scale these features, so today we're open-sourcing a core piece of infrastructure called Tornado, which was originally developed by the FriendFeed team. Tornado is a relatively simple, non-blocking Web server framework written in Python, designed to handle thousands of simultaneous connections, making it ideal for real-time Web services. Tornado is a core piece of infrastructure that powers FriendFeed's real-time functionality, which we plan to actively maintain. While Tornado is similar to existing Web-frameworks in Python (Django, Google's webapp, web.py), it focuses on speed and handling large amounts of simultaneous traffic.

starting point for ressources about Tornado python based webserver and tools

Despite what a lot of people believe, it's easy to introduce memory and resources leaks in .NET applications. The Garbage Collector, or GC for close friends, is not a magician who would completely relieve you from taking care of your memory and resources consumption. I'll explain in this article why memory leaks exist in .NET and how to avoid them. Don't worry, I won't focus here on the inner workings of the garbage collector and other advanced characteristics of memory and resources management in .NET. It's important to understand leaks and how to avoid them, especially since they are not the kind of things that is easy to detect automatically. Unit tests won't help here. And when your application crashes in production, you'll be in a rush looking for solutions. So, relax and take the time to learn more about this subject before it's too late. Table of Content * Introduction * Leaks? Resources? What do you mean? * How to detect leaks and find the leaking resources *

.NETでリークする要因。「Events, or the "lapsed listener" issue」は良く目にする。

dynaTrace Ajax works by sticking low-level instrumentation into Internet Explorer when it launches, capturing any activity that occurs

After reading a recent post by Steve Souders concerning a free tool called dynaTrace Ajax, I was intrigued. It claimed to provide full tracing analysis of Internet Explorer 6-8 (including JavaScript, rendering, and network traffic). Giving it a try I was very impressed. I tested against a few web sites but got the most interesting results running against the JavaScript-heavy Gmail in Internet Explorer 8.

notes on dynatrace - traces/graphs everything that IE Does.

dynaTrace Ajax works by sticking low-level instrumentation when it launches, capturing any activity that occurs.

Jammit is an industrial strength asset packaging library for Rails, providing both the CSS and JavaScript concatenation and compression that you'd expect, as well as YUI Compressor and Closure Compiler compatibility, ahead-of-time gzipping, built-in JavaScript template support, and optional Data-URI / MHTML image embedding. Jammit is an open-source component of DocumentCloud.

Jammit is an industrial strength asset packaging library for Rails, providing both the CSS and JavaScript concatenation and compression that you'd expect, as well as YUI Compressor and Closure Compiler compatibility, ahead-of-time gzipping, built-in JavaScript template support, and optional Data-URI / MHTML image embedding.

cool proposal, seems sane

Funny

This is quite amazing: all resources of a page in 1 HTTP request (excluding the page). Its backwards compatible too.

Comet For The People

Home of the Chromium Open Source Project

A new protocol designed to provide better performance than http

A new experimental protocol to improve HTTP.

mind that there are factors in play other than raw page load performance. As a general rule of thumb, if most of your sprite doesn't contain real image content, you should probably avoid using it. Also, keep an eye out for fu

Note that this is a 1299x15,000 PNG. It compresses quite well — the actual download size is around 26K — but browsers don't render compressed image data. When this image is downloaded and decompressed, it will use almost 75MB in memory (1299 * 15000 * 4).

Manoj Maniraj on the opensource world

(part 2)

In this article we'll take a look at the behavior of the DNS and walk through some experiments you can run to gather valuable data about your users' network performance.

The Domain Name System (DNS) is part of the "dark matter" of the internet. It's hard to observe the DNS directly yet it exerts an obscure, pervasive influence without which everything would fly apart. Because it's so difficult to probe people tend to take it for granted, which I think is a mistake. DNS problems can hurt the speed and reliability of your applications without you even noticing. In this article we'll take a look at the behavior of the DNS and walk through some experiments you can run to gather valuable data about your users' network performance.

s an obscure, pervasive influence without which everything would fly apart. Because it's so difficult to probe people tend to take it for granted, which I think is a mistake. DNS problems can hurt the speed and reliability of your applications without you even noticing. In this article we'll take a look at the behavior of the DNS and walk through some experiments you can run to gather valuable data about your users' network performance.

The Domain Name System (DNS) is part of the "dark matter" of the internet. It's hard to observe the DNS directly yet it exerts an obscure, pervasive influence without which everything would fly apart.

This is a unique YDN blog post.

5. Index and Use Same Column Types for Joins

** Posted using Viigo: Mobile RSS, Sports, Current Events and more **

20 Best practices

A nice overview of some of the more popular patterns in NoSQL architecture

To me, the most important element was actually testing everything as we went. By putting in a little extra work, we could quickly gauge which ad creative, landing page and advertiser was giving us the best results and react accordingly.

Understanding Caching in Hibernate – Part Three : The Second Level Cache Performance, Scalability and Architecture – Java and .NET Application Performance Management (dynaTrace Blog)

In particular I read a whitepaper several years ago a

In the last posts I already covered the session cache as well as the query cache. In this post I will focus on the second-level cache. The Hibernate Documentation provides a good entry point reading on the second-level cache. The key characteristi

ふむ。

HTML高速化まとめ

As I grew older, this conclusion lay dormant and unexamined in my mind. RPGs continued to be my favorite genre. I relished the opportunity to watch interesting, lovable characters develop and interact in epic storylines. (Comparatively interesting and lovable, anyway - say what you will about Cecil, but his quest for redemption revealed a lot more depth than Mega Man's quest to shoot up some robots.) And I loved feeling like a hero. I saved the world in Final Fantasy IV, again in Lufia II, then again in Chrono Trigger.

Database operations often tend to be the main bottleneck for most web applications today. It's not only the DBA's (database administrators) that have to worry about these performance issues. We as programmers need to do our part by structuring tables properly, writing optimized queries and better code. Here are some MySQL optimization techniques for programmers.

uWSGI is a fast (pure C), self-healing, developer-friendly WSGI server, aimed for professional python webapps deployment and development.

they

Today, as part of our efforts to make the web faster, we are announcing Google Public DNS, a new experimental public DNS resolver.

I'm in two minds about whether to use them or not. But it's good that there's a DNS provider I can fall back on if my ISP's DNS goes tits up that isn't sodding OpenDNS.

Google何でもやるなー. すごい.

MySQLの負荷テストに便利らしい。

Namebench hunts down the fastest DNS servers available for your computer to use. namebench runs a fair and thorough benchmark using your web browser history, tcpdump output, or standardized datasets in order to provide an individualized recommendation.

Are you a power-user with 5 minutes to spare? Do you want a faster internet experience? Try out namebench. It hunts down the fastest DNS servers available for your computer to use. namebench runs a fair and thorough benchmark using your web browser history, tcpdump output, or standardized datasets in order to provide an individualized recommendation. namebench is completely free and does not modify your system in any way. This project began as a 20% project at Google. namebench runs on Mac OS X, Windows, and UNIX, and is available with a graphical user interface as well as a command-line interface.

Summary of the Facebook architecture and the bottlenecks they have had to work around

After considering a variety of data clustering algorithms, found that there was very little win for the additional complexity of clustering. So at Facebook, user data is randomly partitioned across indiviual databases and machines across the cluster. Hence, each user access requires retrieving data corresponding to user state spread across hundreds of machines. Intra-cluster network performance is hence critical to site performance. Facebook employs memcache to store the vast majority of user data in memory spread across thousands of machines in the cluster. In essence, nodes maintain a distributed hash table to determine the machine responsible for a particular users data. Hot data from MySQL is stored in the cache. The cache supports get/set/incr/decr and

Great essay describing the perception of software performance and the various time ranges that matter. Good content and great source of references to other source material on the topic.

Designing and Engineering Time

When you need to choose which part of your application to focus on speeding up, understanding where and why users will perceive performance problems is key. You can't and shouldn't optimize everything. Remember, perception is reality. No mater what your metrics say, if the user thinks your application is slow, it is.

"Failing to specify reasonable performance requirements makes it very difficult to verify that your software is actually meeting your users' performance expectations." … with a good overview of Seow's timings.

very useful thoughts on setting performance expectations.

よい記事。フロントエンドエンジニアの観点からの、パフォーマンス向上方法。

PageDetailerとYFlowによるパフォーマンス改善ポイントの洗い出し

http://www.alphaworks.ibm.com/tech/pagedetailer あとで計測してみよう。

IBM PageDetailer、そういうのもあるのか

>10. Minify JS これは、JavaScriptの改行や無駄なスペースを削除することでファイルサイズを減らそう、という項目です。 個人的なオススメはJSMinというツールです。

実質 YSlow の解説。わかりやすい

YSlowの解説

We're going to keep this post lean and mean, and get down to business with 10 Tips that will keep your Flex applications fast, lean, and responsive. The tips are focused around three best practices rules. Rule # 1: Clean up after yourself -- In general, it is good practice to maintain clean code. Not only in the sense of having properly formatted and readable code, but also code that leaves nothing behind... no memory leaks, no cpu hogs, nothing but a clean object that can be reclaimed by the GC.

PHPでのプロファイリングというとXdebugでファイルを吐き出してWinCacheGrindやKCacheGrindで読み込む（ファイルを吐き出したファイルをGETして、ソフトに読み込ませる）が定番ですが、XHProf を使えば、ブラウザ上で、プロファイリングが出来るみたいです。

XHProf Documentation (Draft) PHPプログラムを解析して何処が重いか？がブラウザ上で簡単に分かる「XHProf」。 通常、PHPでのプロファイリングというと、Xdebugでファイルを吐き出して、WinCacheGrindやKCacheGrindで読み込むというのが定番です。 ですが、この方法だと、ファイルを吐き出したファイルをGETして、ソフトに読み込ませる、というちょっと面倒な手順が必要でした。 XHProf を使えば、ブラウザ上で、プロファイリングが出来るみたいです。 XHProfの特徴 まず、セグメントごとの実行時間やメモリ利用の状況なんかがブラウザで見れます。 プログラムの構造を把握するのにも使えます。

PHPのプログラムを解析して重い処理をブラウザ上に表示する

We've often been asked what makes Google Chrome so fast -- from its snappy start-up time and fast page-loading, to the ability to run complex web applications quickly. To walk through some of the thought processes and technical decisions involved in making Google Chrome a fast browser, we've put together three technical interviews on DNS pre-resolution, the V8 JavaScript engine, and DOM bindings. In a future post, we'll also cover other important areas like WebKit and UI responsiveness.

Spoiler alert: DNS pre-resolution, the V8 JavaScript engine, and DOM bindings

Chrome does indeed has a fast.

サーバのネットワーク速度の調査/測定方法

ethtool しらなかった．

A unique, comprehensive, accurate & free Windows (and Linux/Wine) utility to determine the exact performance of local and remote DNS nameservers . . .

A unique, comprehensive, accurate & free Windows (and Linux/Wine) utility to determine the exact performance of local and remote DNS nameservers

As

Alex Miller's technical blog on Java, concurrency, programming, design, languages, and more

Hibernate et la gestion du cache

This also shows that for massively concurrent problems, such as lots of parallel comet connections, the GIL in Python is a non-issue as we handle the concurrent connections in a single thread. In this post i am going to look at a selection of asynchronous servers implemented in Python.

How to Succeed at Programming

Awesome.

"I for one, welcome our new overlords"

Speed Tracer is a Google Chrome extension that enables developers to identify performance problems in their web apps using a "Sluggishness Graph," in combination with many other metrics.

12/08/2009 07:14:00 PM Do you ever wonder what's going on inside the browser when a webpage doesn't load or respond as quickly as it should? Many developers do, especially when trying to build powerful web applications for their users. But up until now, it's been difficult for developers to identify problems in a slow-to-respond application. So, tonight at Google Campfire One, we're happy to announce that we're adding a new tool to Google Web Toolkit called Speed Tracer. Speed Tracer is a Google Chrome extension that enables developers to identify performance problems in their web apps using a "Sluggishness Graph," in combination with many other metrics. In the spirit of clean, simple design, developers need only look at the Y-Axis of their application's Sluggishness Graph to see how they're doing: * If the y-axis is close to zero, then the app is fast * If the y-axis registers around 100%, then the app is, well, sluggish And in either case, Speed Tracer provides lots of ad

Firefox　ファイヤ

よくある構成っちゃ、よくある構成。MySQL ClusterとかMySQL Proxyとかの完成度があがっていくとこの部分の構成がもっとシンプルかつ強いシステムになっていくのかも

「dual master + ソフトウエアロードバランサ + Nagios」「masterサーバーに障害があった場合には、(Nagios のイベントハンドラで)それに直結する slave のヘルスチェック用ポートを閉じる」

事例

dual master, ソフトウェアロードバランサ, 仮想DNS, gethostbyname書き換え, masterが片方落ちたら直下のslaveもnagiosのイベントハンドラで落として一貫性保つ

10個しかないんかな

article about long vs. short javascript timers, etc

How Google Works

'...while both [Google] search queries and processing power have gone up by a factor of 1000, latency has gone down from around 1000ms to 200ms. Crawler updates now take minutes compared to months in 1999.'

Configuring nginx as load balancer

Nginx

Whether you run Windows 7, Vista, or XP, these 25 tricks will make your PC faster, safer, and even more fun to work with.

Website performance is a hugely important topic, so much so that the big companies of the Web are obsessed with it. For the Googles, Yahoos, Amazons and eBays, slow websites mean fewer users and less happy users and thus lost revenue and reputation.

Website performance is a hugely important topic, so much so that the big companies of the Web are obsessed with it. For the Googles, Yahoos, Amazons and eBays, slow...

AMD Phenom 9750 Quad-Core is the most bang for the buck, according to Paul's analysis (nice!)

Les processeurs classés par leur rapport performances / prix. Qui est en tête ? AMD !

CPU Comparisons wrt price and performance

As a self confirmed conference junkie I speak at a dozen events each year, and attend many more. As such I’ve probably seen close to a thousand talks over the last five years. Because of this I’ve got a pretty good idea what makes for an exciting talk and how you can guarantee your session will suck. As somebody who also organises two conferences, UX London and dConstruct I’m really keen on getting new talent into the speaking circuit while still maintaining quality. As such I’ve put together a quick guide to help both new and experienced speakers kick arse/ass. Most of these tips aren’t new, but you’ll be surprised how few people actually follow them. However if you do, you’ll be well on your way to being the next Jeff Veen, Jared Spool or Jason Santa Maria.

nest loops too many....

Speed up your JavaScript,

Last week, I covered the first reason why JavaScript can take too long to execute: too much happening in a loop. There's a similar problem with functions in

WordPressをさらに高速化するために青い人の提案でAPCを入れることに。導入して正解。Load Averageもぐっと下がっていい感じ。 なお、APCはPHPの中間コードやらキャッシュやらを最適化して高速化してくれるモジュールです。以下、簡単に導入メモ。

Steve Jobs presentation techniques

Hanushek recently did a back-of-the-envelope calculation about what even a rudimentary focus on teacher quality could mean for the United States. If you rank the countries of the world in terms of the academic performance of their schoolchildren, the U.S. is just below average, half a standard deviation below a clump of relatively high-performing countries like Canada and Belgium. According to Hanushek, the U.S. could close that gap simply by replacing the bottom six per cent to ten per cent of public-school teachers with teachers of average quality.

8bit-PNG

Yahoo!ニュースが2009年4月27日にリニューアルしました。今回のリニューアルでは、お客様に快適にサイトを利用していただけるよう最速でページを表示させることに重点をおきました。お客様がウェブを閲覧するのは1日の中のほんの限られた時...

How to speed up your computer.

useful advise...

large images, multiple pieces of Javascript, and hefty CSS files. All of these can contribute to a website that is less than optimized and may run slower and become irritating to the end user.

In this presentation from the JVM Languages Summit 2009, Cliff Click discusses the Von Neumann architecture, CISC vs RISC, the rise of multicore, Instruction-Level Parallelism (ILP), pipelining, out-of-order dispatch, static vs dynamic ILP, performance impact of cache misses, memory performance, memory vs CPU caching, examples of memory/CPU cache interaction, and tips for improving performance. -- It's a shame I would of liked to see the presentation on their hardware transactional memory implementation and why "it doesn't work as all the academics would have you believe."

In this presentation from the JVM Languages Summit 2009, Cliff Click discusses the Von Neumann architecture, CISC vs RISC, the rise of multicore, Instruction-Level Parallelism (ILP), pipelining, out-of-order dispatch, static vs dynamic ILP, performance impact of cache misses, memory performance, memory vs CPU caching, etc.

Helium is a tool for discovering unused CSS across many pages on a web site. The tool is javascript-based and runs from the browser.

Helium - javascript tool to scan your site and show unused CSS

integrate this into release procedure

determine unused css

tool for identifying unused css

Typically excellent post from Ilya Grigorik.

An indepth look at disk i/o throughut, measurement and performance monitoring within Linux

PNG Image Optimization

5-Minute PNG Image Optimization • Perishable Press

var k=t.value;k!=h&&X(0);h=k というコードが毎秒100回実行されている。

具体的には、var k=t.value;k!=h&&X(0);h=k というコードが毎秒100回実行されている

タイマーでしか日本語未確定文字列の変更をチェックできないというのがそもそもなんとかならんのか。

* Googleのトップページは開いているだけでCPUを使うので、用事がないときは開かないようにしよう。 * Amazon、YouTube、IEEEなども同様に、開いているだけでCPUを使うので、用事がないときは開かないようにしよう。 * YOMIURI ONLINEとBing（のトップページ）にもすこし気をつけよう。

あとで

awesome article!

This tale of two boys, and of the millions of kids just like them, embodies the most stunning finding to come out of education research in the past decade: more than any other variable in education—more than schools or curriculum—teachers matter.

After his two years were up, Farr went to law school, as planned.,

Worth having every staff read and debate this article.

Face

"an easily-interpreted heads-up display of 26 popular third party APIs. The big boys like Facebook, Twitter and Flickr are all present and accounted for, and other services like Salesforce, and Posterous are supported also."

主要サービスAPIの稼動状況をモニターしてくれるサイト

500 Internal Server Error

Good, quick introduction to vmstat, iostat, and top for checking Linux performance stats.

what ought to be common knowledge about vmstat, iostat, and top

basics.

Description. You want to read about the code structure of the new whitehouse.gov website on this historic Inauguration Day of the 44th president of the USA. The site is built on ASP.NET.

"The whitehouse.gov has a page weight of 821 KB and loaded in 1.58 seconds on my cable modem. This is around average for new and graphically-oriented sites." Say what??

javascript performance memoization programming memoizer

Yes, memoization is a neat concept. But why use it rather than just hand-coded caching mechanisms? It’s easy enough to write a caching routine, right? Here are a few good reasons: * hand-coded caching mechanisms obfuscate your code * multi-variate caching routines are bulky in Javascript * fewer lines of code means fewer bugs * Java programmers will think more highly of you*

With HipHop we've reduced the CPU usage on our Web servers on average by about fifty percent, depending on the page. Less CPU means fewer servers, which means less overhead. This project has had a tremendous impact on Facebook. We feel the Web at large can benefit from HipHop, so we are releasing it as open source this evening in hope that it brings a new focus toward scaling large complex websites with PHP. While HipHop has shown us incredible results, it's certainly not complete and you should be comfortable with beta software before trying it out.

HipHop for PHP. With HipHop we've reduced the CPU usage on our Web servers on average by about fifty percent, depending on the page. Less CPU means fewer servers, which means less overhead.

Facebook is a social utility that connects people with friends and others who work, study and live around them. People use Facebook to keep up with friends, upload an unlimited number of photos, post links and videos, and learn more about the people they meet.

-ImageMagick: to identify the image type and to convert GIF files to PNG files. -pngcrush: to strip unneeded chunks from PNGs. We are also experimenting with other PNG reduction tools such as pngout, optipng, pngrewrite. Hopefully these tools will provide improved optimization of PNG files. -jpegtran: to strip all metadata from JPEGs (currently disabled) and try progressive JPEGs. -gifsicle: to optimize GIF animations by stripping repeating pixels in different frames.

Smush.it uses optimization techniques specific to image format to remove unnecessary bytes from image files. It is a "lossless" tool, which means it optimizes the images without changing their look or visual quality.

Note about Code-State-Cache-Data (CSCD) pattern in scalable web applications.

Short Article propounding the use of a "Code-State-Cache-Data-Architecture" (CSCD) instead of just CD or CCD applications. Basically saying that you should forget about stateful apps if you wan't maximum performance...

Application state - Data you can restore from the database or afford to lose if server is restarted (logged in users). He recommends storing this in-memory. "Application state goes into an in-memory key-value store like Tokyo Tyrant. Cache data goes into Memcached. Persistent data goes into a database"

"What he needs is the insight to identify state, cached data and persistent data in his application. Application state goes into an in-memory key-value store like Tokyo Tyrant. Cache data goes into Memcached. Persistent data goes into a database. Note that the seperation of code and application state may be beneficial later, because it allows you to scale easily by adding new memory servers. ... Let's call this the Code-State-Cache-Data (CSCD) pattern. What Damian originally had was a Code-Data (CD) pattern, and later he optimized to get a Code-Cache-Data (CCD) pattern"

Good overview of Django Caching Techniques

denormalization

A paginated display is one of the top optimization scenarios we see in the real world. Search results pages, leaderboards, and most-popular lists are good examples. You know the design pattern: display 20 results in some most-relevant order. Show a "next" and "previous" link. And usually, show how many items are in the whole list and how many pages of results there are. Rendering such a display can consume more resources than the entire rest of the site! As an example, I'm looking at slow log analysis results (with our microslow patches, set to log all queries) for one client; the slow log contains 6300 seconds' worth of queries, and the two main queries for the paginated display consumed 2850 and 380 seconds, respectively.

Rendering such a display can consume more resources than the entire rest of the site!

A paginated display is one of the top optimization scenarios we see in the real world. Search results pages, leaderboards, and most-popular lists are good examples.

Perl script for reporting back on your MySQL config.

Debugging and Tuning MySQL performance

Handy script to gather suggestions on mysql tuning

Stay curious!

Implementing AJAX technology can be a hit or miss thing. Do it well and you'll have users raving over the slickness it provides to the general user experience

ほえー。どうなってんだろ。

Plugging memory leaks in JavaScript is easy enough when you know what causes them. In this article authors Kiran Sundar and Abhijeet Bhattacharya walk you through the basics of circular references in JavaScript and explain why they can cause problems in certain browsers, especially when combined with closures. After seeing some of the common memory leak patterns you should watch out for, you'll learn a variety of easy ways to work around them.

Memory Leaks in Javascript -> wie wo was warum erklärt dieser Artikel ganz nett

"YouTube speed-tester that tells you how your ISP stacks up against other ISPs in your town and country, to give you the ability to compare your speed numbers with other users in your region."

Benchmarks ISP speed using you tube videos

I guess the conclusion is that there’s no use in preempting the technological progress of tomorrow. Machines will get faster and cheaper all the time, but you’ll still only have the same limited programming resources that you had yesterday. If you can spend them on adding stuff that users care about instead of prematurely optimizing for the future, you stand a better chance of being in business when that tomorrow finally rolls around.

From 37signals

VerkkoStadi Technologies is looking for a Hardcore PHP Developer. See more on the Job Board.

Google謹製ウェブサイトパフォーマンス測定アドオン

YahooのYSlow的な

The 3 pillars of our Rails monitoring stack We break Rails monitoring into the 3 parts below (along with the tools we use): Process Monitoring System Performance Exception Notifications

InnoDBは行ロックに対応。6000万レコード。。。

Web アプリケーションとは切っても切れないセッション機構。DB ベースでセッション管理を行なって得られた知見と、それを元に考察した結果をまとめてみます。

The underground world of neuroenhancing drugs. Such is the zeitgeist.

Brain Gain ?

using mind enhancing drugs to improve performance

The underground world of “neuroenhancing” drugs.

[object Object]

"The following information is meant to provide documentation on how others can recreate the benchmark trials used in our SIGMOD 2009 paper."

A Comparison of Approaches to Large-Scale Data Analysis: MapReduce vs. DBMS Benchmarks

Mongo DB Production

Interesting blog post detailing production experiences with mongodb.

Taking an event that fires multiple times in a short period of time, and treating them as one event.

パフォーマンス、ユーザー動作の休止を検知する、バウンス(スイッチの切り換えサイクルが収束すること)、Throttling(イベント発生数を減らす /mousemoveイベントなど)、発生回数などは保持する、一定期間(threshold)イベントが発生しなくなってから処理を実行する/イベントをまとめる、execAsapがtrueの場合は先に処理を行い一定期間(threshold)処理を受け付けない、timeoutが空かどうかで判定している/高速にsetTimeoutとclearTimeoutを繰り返す、←ツールチップ表示のトリガの動作に近い

via youpy、パフォーマンス、ユーザー動作の休止を検知する、バウンス(スイッチの切り換えサイクルが収束すること)、Throttling(イベント発生数を減らす/mousemoveイベントなど)、発生回数などは保持する、一定期間(threshold)イベントが発生しなくなってから処理を実行する/イベントをまとめる、execAsapがtrueの場合は先に処理を行い一定期間(threshold)処理を受け付けない、timeoutが空かどうかで判定している/高速にsetTimeoutとclearTimeoutを繰り返す、←ツールチップ表示のトリガの動作に近い

デバウンス 短時間に発生する複数のイベントをまとめる setTimeout/clearTimeout

timeout id をクロージャにして関数を返す関数を作ることで、resize などの操作が続けて起こる場合は、操作が全部終わってから特定時間待つように。debouncing というらしい。 http://invisibleblocks.wordpress.com/2009/10/20/a-javascript-war-story/

WebKit browsers paved the way with CSS based gradients. Now Firefox 3.6 is out and is supporting them as well, which makes using them for progressive enhancement all the more appealing. More good news, CSS3 gradients fall into the camp where you can specify fallbacks (i.e. images) so that browsers that don’t support them just use the image instead. But wait… if you need to use an image anyway, why bother with declaring the gradient with CSS? That is kind of how I felt for a long time, but there is one important aspect that makes it worth it: browsers that support them don’t load the image fallback. One less HTTP Request = all the faster your site will load.

"# LuxIO (ラックスIO)"# 普通のB+-tree # 特徴1 * mapped index * index部を全部mmap o index部を実メモリより小さいシステムが対象 # 特徴2 * 長いvalue * 4Gまで * node size(page size)をこえたvalueも余計なオーバーヘッドなしで扱える # 特徴3 * 効率的なappend * paddingなしでLinkedListのデータ構造 # SSDに向いてる？ # 使い道 * key-valともに小さいデータで構想なアクセスが必要な場合 * 実メモリ以下のデータベースという制約あり * 大きなvalueを扱いたい場合 * 大きなvalueをどんどん追記したい # 向かない処理 * 削除が多い処理 * 小さいデータをたくさんリンク o seekのオーバーヘッドが大きすぎる * Read,Writeの激しいアプリ # 分散はたぶんしない # Hashはつくるかも # read lockはなくしたい * 読み込みを重きをおく"

Key-Value型データ設計に関して。いくつかのシステムの特徴などのメモ。

tips to tweak vista for better gaming performance

Windows Vista was heralded by its creators as being a speedy operating system. However, it didn't take long for users to realise that Vista's performance was generally no better than Windows XP, and in many cases was actually worse. Working with a PC that isn't performing to its maximum potential can be a frustrating experience, but this is particularly true if the machine is used for gaming. But there are a huge number of tweaks that can be applied to help make working with Vista less exasperating.

5 Ways to Speed Up Your Rails App

good explanation of Ruby's threads & stack implementation

6s

ruby 1.8 mri assembly threads

SQL optimization

10 sql tips to speed up your database http://bit.ly/9uIi6k #sql

「昔はWebブラウザの新バージョンのリリースには1年とか1年半かかっていました。しかし、われわれはWebブラウザの世界にも、Webアプリケーションと同じ速度で革新をもたらしたいのです」。

スクリプトは最後に置く

データベースパフォーマンスアップの教科書 基本原理編

どこの現場に行っても正解を導く方程式は一緒なので応用が利く Oracle、SQLServer、MySQLと色々なDBのチューニングをしてきましたが、 どれもRDBの理論に基いているので基本原理を知ればチューニングは可能なはず インデックススキャンの種類や、実行計画の読み方もわかりやすく詳しい

You just hit the power button your PC and now you've got enough time to brew a fresh pot of

Benchmarks super intéressant de quasi tout les webservers python (de mod_wsgi à Twisted en passant par CherryPy). Je ne les connaissais pas tous et certains semblent vraiment fort intéressant (je pense notamment à uWsgi).

Faster JPEG Encoding with Flash Player 10 http://bit.ly/cHrQoO #flash #jpeg

作者對Flash Player10作了JPG輸出優化(比corelib的版本快了2.X以上)

JPEGEncoder

replacement jpeg encoder class

Vectorを使ったJpegエンコーダクラス

trics on eBay’s main Teradata data warehouse include: * >2 petabytes of user data

Millions of queries per day

Statistieken over de databaseverwerking van ebay

Performance is something you don’t often think about. You assume that if it loads quickly enough for you then everyone’s happy. Someone commented a while back saying that it takes quite long for my pages to load so I optimised it a tad and thought I’d share a few quick tips with you.

# # Scaling practices turn a relational database into a non-relational database. To scale at Digg they followed a set of practices very similar to those used at eBay. No joins, no foreign key constraints (to scale writes), primary key look-ups only, limited range queries, and joins were done in memory. When implementing the comment feature a 4,000 percent increase in performance was created by sorting in PHP instead of MySQL. All this effort required to make a relational database scale basically meant you were using a non-relational database anyway. So why not just use a non-relational database from the start?

As Digg started out with a MySQL oriented architecture and has recently been moving full speed to Cassandra, his observations on some of their lessons learned and the motivation for the move are especially valuable. Here are some of the key takeaways you find useful:

RT @Sebdz: RT: @programmateur: Digg: 4000 % performance increase by sorting in PHP rather than MySQL (via @mrboo) - http://bit.ly/ckma10

♻ @n1k0: "Scaling practices turn a relational database into a non-relational database" http://n1k.li/4v (via @nsilberman)

Typically for relatively static data sets, relatively low query volumes, and relatively high latency requirements.

Photographs of people who Meade painted on

Painting real people like paintings.

painting on human

Very inspirational artist, great work mix of painting and photography.

JDbMonitor is a tool to monitor & analyse database performance for any Java application. Easily determine your application's database performance and analyse problems down to specific SQL statement.

Tool for monitoring JDBC database activity

Monitor JDBC Performance For Slow SQL Queries

CSS Sprites tekniği hakkında makale

What do you think? Should we reconsider the use of mega sprites in CSS development? Do the statistics in favour of the savings on HTTP requests warrant the use of...

CSS sprites, muito util e interessante a tecnica, neste post podemos ver que ele é util em casos de estilizacao... mas nunca no conteudo

Learn to scale your UNIX® Python applications to multiple cores by using the multiprocessing module which is built into Python 2.6. Multiprocessing mimics parts of the threading API in Python to give the developer a high level of control over flocks of processes, but also incorporates many additional features unique to processes.

In a previous article for IBM® developerWorks®, I demonstrated a simple and effective pattern for implementing threaded programming in Python. One downside of this approach, though, is that it won't always speed up your application, because the GIL (global interpreter lock) effectively limits threads to one core. If you need to use all of the cores on your machine, then typically you will need to fork processes, to increase speed. Dealing with a flock of processes can be a challenge, because if communication between processes is needed, it can often get complicated to coordinate all of the calls. Fortunately, as of version 2.6, Python includes a module called "multiprocessing" to help you deal with processes. The API of the processing module has some similarities to the way the threading API works, but there are also few differences to keep in mind. One of the main differences is that processes have subtle underlying behavior that a high-level API will never be able to completely abst

physical

Useful, in-depth discussion of how memory is handled on Windows and Linux with respect to Java Virtual Machines. How to diagnose memory problems; dealing with Java heap as well as native memory exhaustion issues. Source code / demo

Processors are described as being a certain number of bits. This normally refers to the size of the registers, although there are exceptions — such as 390 31-bit — where it refers to the physical address size. For desktop and server platforms, this number is 31, 32, or 64; for embedded devices and microprocessors, it can be as low as 4. The physical address size can be the same as the register width but could be larger or smaller. Most 64-bit processors can run 32-bit programs when running a suitable OS.

http://groups.csail.mit.edu/cag/ps3/lectures.shtml

Några braiga tips och nyheter från jQuery 1.4.

31 jQuery Snippets That Will Help Make You A JavaScript Pro /by @addyosmani http://j.mp/d90IOM #jquery #webdesign

ASの高速化Tips

ActionScript の最適化って色々なサイトに載っていますが、wonderfl にまとめて載っておくとコードと動きを同時に確認できるし、自分のためにも便利だと思って色々と投稿しました。コードへのリンクに個人的な私見を加えてご紹介します。ただ、人によって意見が異なるかもしれないので、コードと動きを直接確認しておくことをお勧めします。この処理はおかしいんじゃないか？とかありましたらコメントください。 変数名の長さによる処理速度の違い 変数名の長さによる違いはありません。ですので変数名は、他の人が見やすい・自分が後で確認しても分かり易いような名前を付けておいた方が良いです。 変数を参照する際の処理速度の違い 上のコードでは _getPi <<< Math.PI <<< MyMath.PI = Main.PI < PI = _pi = ns::_pi = pi という結果で、ビルトインクラスのプロパティアクセスは若干重いので、ループ内で大量に参照する場合は変数に格納しておく方が良いです。また、getter アクセスの実態は関数ですので結構重いみたいです。MyMath.PI や Main.PI は、他の参照方法に比べると一階層下がるので若干重いですが、100 万回もループしての結果なので、あまり気にする必要はないんじゃないかと思います。ただ、注意事項が一つありますので「色々な整数化手段での処理速度の違い」も目を通しておいて下さい。 if … else と switch での処理速度の違い if … else 文は比較回数が少ない場合は軽いですが、比較回数が増えると switch 文の方が高速です。ただ、100 万回も処理させて数ミリ秒の違いですので、臨機応変に見やすい方を記述しておけば良いんじゃないかと思います。 色々な整数化手段での処理速度の違い

ActionScript の最適化 Tips

「FasterFoxLite」はFirefoxのネット接続速度を最大限引き出してくれるアドオン。今回は、カスタム設定で劇的に速くなる動作環境を作ってみる。

あとで試してみるけど、火狐たんの寿命が縮まってるような・・・。

最大限

free tools for Windows will help breathe new life into your old machine

You've done everything you can to get your computer back up to speed. You've used all the tools there are to save space, defrag, and get rid of junk.   You've

Linux boot fast together with Windows

Une mini-distribution Linux commerciale qui boot en 15 secondes.

You may have heard that here at Google we're obsessed with speed, in our products and on the web. As part of that effort, today we're including a new signal in our search ranking algorithms: site speed. Site speed reflects how quickly a website responds to web requests.

@dworni Danke fürs Kompliment! Dieses Merkmal gewinnt an Gewicht, wenn man Google's Ranking Algorithmus betrachtet: http://bit.ly/baZCCs – cmsbox (cmsbox) http://twitter.com/cmsbox/statuses/12153045861

Cómo jugar con los refrescos de caché para diferentes tipos de archivos en un proxy squid.

Will look into implementing this at the office some time...

refresh_pattern ^ftp: 1440 20% 10080 refresh_pattern ^gopher: 1440 0% 1440 refresh_pattern -i \.(gif|png|jpg|jpeg|ico)$ 10080 90% 43200 override-expire ignore-no-cache ignore-no-store ignore-private refresh_pattern -i \.(iso|avi|wav|mp3|mp4|mpeg|swf|flv|x-flv)$ 43200 90% 432000 override-expire ignore-no-cache ignore-no-store ignore-private refresh_pattern -i \.(deb|rpm|exe|zip|tar|tgz|ram|rar|bin|ppt|doc|tiff)$ 10080 90% 43200 override-expire ignore-no-cache ignore-no-store ignore-private refresh_pattern -i \.index.(html|htm)$ 0 40% 10080 refresh_pattern -i \.(html|htm|css|js)$ 1440 40% 40320 refresh_pattern . 0 40% 40320

These are all mysql oriented, but it sure seems like there are some fantastic principles to be pulling from here. Ex "covering indexes; orders-of-magnitude improvements." Or one on optimizing disk i/o.

Slides from a great variety of sessions @ Percona Performance Conference 2009 (April)

slides of the conference are available onliny

DNS is a great example of a service that couldn't possibly work on paper, but performs spectacularly in practice, even with a hodge-podge of implementations all over the Internet.

DNS is a great example of a service that couldn't possibly work on paper, but performs spectacularly in practice, even with a hodge-podge of implementations all over the Internet. First, the authoritative DNS servers responds with a Time To Live (TTL) timestamp for every record (which you should keep fairly low in a virtual deployment environment), then the upstream DNS servers cache that same data, albeit usually with different policies (determined by the ISP). And finally, your router, OS, and the browser all have their own and independent DNS caches. (Firefox 2/3 caches all DNS records for a 1 minute, IE 5/6/7 for 15 minutes). Talk about a mess!

Good tips on using DNS in the cloud, and in particular using a staging environment that is switched over (via DNS) to a production environment.

"This results in an increase from 500 requests/sec to 7000 requests/sec when using Sinatra+Thin+Epoll+Threads. That is pretty ill." -- Joe Damato

On top of all that, this patch helps with Ruby’s green threads, too. If the epoll_wait causes a Ruby event to fire and that event creates a Ruby thread, that Ruby thread gets an entire copy of the existing stack. Each time that thread is switched into and out of, that thread stack has to be memcpy’d into and out of place. Reducing those memcpys by ~800,000 bytes is a HUGE performance win. Want to learn more about threading implementations? Check out my threading models post: here. Fixing this turned out to be pretty simple. A six (6!!) line patch: * Speeds up GC by 2-3x because of the huge decrease in stack frame size. * Fixes an open bug in EventMachine where using threads with Epoll causes lots of slowness. The reason is that each thread will inherit an ~800,000 byte stack that gets copied in and out every context switch. * This results in an increase from 500 requests/sec to 7000 requests/sec when using Sinatra+Thin+Epoll+Threads. That is pretty ill.

l in all, a productive debugging session lasting about an hour. The result was a simple patch, with 2 big performance improvements.

Say NO to fat CSS and js files with this #php script and mod_rewrite

twitter DB fan out　メール

TwitterのDB構成

How To Diagnose a Suddenly Slow Windows Computer? -- article related to Ask Slashdot, Windows, and IT.

Interesting, most of the comments are related to a soon to fail HD (with suggestions to test it)

Caching is easy to screw up. Usually it's a manual process which is error-prone and tedious. It's actually quite easy to cache, but knowing when to invalidate which caches becomes a lot harder. There is a subset of caching the caching problem that, with Django, can be done quite easily. The underlying idea is that every Django model has a primary key, which makes for an excellent key to a cache. Using this basic idea, we can cover a fairly large use case for caching, automatically, in a much more deterministic way. Let's begin.

some sample caching code

Distributed systems are not typically a place where domain driven design is applied. Distributed processing projects often start with an overall architecture vision and an idea about a processing model which basically drives the whole thing, including object design if it exists at all. Elaborate object designs are thought of as something that just gets in the way of distribution and performance, so the idea of spending time to apply DDD principles gets rejected in favour of raw throughput and processing power. However, from my experience, some more advanced DDD concepts can significantly improve performance, scalability and throughput of distributed systems when applied correctly.

One of the most important building blocks of DDD that can help in distributed systems are aggregates. Unfortunately, at least judging by the discussions that I’ve had with client teams over the last few years, aggregates seem to be one of the most underrated and underused building blocks of DDD. I’m probably as guilty as anyone else of misusing aggregates and it took me quite a while to grasp the full potential of that concept. But from this perspective I think that getting aggregates just right is key to making a distributed system work and perform as expected.

RT @kadavy WordPress Optimization: How I Reduced Page Load Time by 75% http://bit.ly/d2Gfga

JavaScript 等の速度を測定する。Firefox add-on

Google Fellow Jeff Dean gave an excellent keynote talk at the recent WSDM 2009 conference that had tidbits on Google I had not heard before. Particularly impressive is Google's attention to detail on performance and their agility in deployment over the last decade.

一些有用的代码收集

Frammenti di codice C per trucchetti

the bit twiddler

Now I am in no way advocating that you lose the abstraction that jQuery provides, but rather, providing a faster alternative that doesn't require the use of jQuery. Always keep in mind that while not as elegant, native javascript can do what you want faster.

also includes interesting links

page speed optimization yslow

GTmetrix can help you develop a faster, more efficient, and all-around improved website experience for your users.

> google-perftoolsには次に挙げる4つのツールが含まれている。* 高速メモリアロケータ TCMalloc * ヒープチェッカー * ヒーププロファイラ * CPUプロファイラ

They are still re

Ruby is in a very bad place right now. It’s no longer cutting edge, it’s technically stagnant, is in implementation limbo, and just isn’t… well… fun, anymore.

Dave Kirin on Ruby's growing pains - "Perhaps the most frustrating part about Ruby, to me, is the outrageously outdated state of the current Ruby interpreter. There is basically no way to avoid writing software that leaks memory. It will happen, you just have to make it leak as little as possible. I still remember the massive effort that Tom Preston-Werner went through to get a relatively simple program like God.rb to not leak memory… and it still leaks memory!": 2008-11-20: kd.to_tumblr

Let me start by saying that I’ve been a longtime fan of Ruby. I’ve been a member of the #caboose cabal forever, and I’ve written hundreds of thousands of lines of ruby over the course the last 6 years. I’ve drank the Ruby kool-aid, helped to start two Rails Startups and integrated a lot of code into Ruby. I fought tooth and nail to get Lockheed Martin to include Ruby deliverables in their RSA2 standardization project (didn’t you know? Ruby helps launch rockets!)

Why Ruby is dying

t Level Cache (aka Transaction layer level cache)

net.sf.ehcache.hibernate.Provider

performance tuning tips for hibernate.Best article

Steve Huffman on Lessons Learned at Reddit By Keir Whitaker

[...] what could be done to tweak Mac OS X in order to, at least minimize the write amplification problem and also optimize the space used – yes you know the €/MB ratio is high on SSDs. Most of these tweaks, besides providing for a longer lifespan for SSD disks, should improve overall system performance even on an non SSD disk. Of course you will use them at your own risk…

Ok, I have an Intel X-25M 160 GB SSD coming and I’m on a VERY GEEKY mood… so I decided to poke around a little on what could be done to tweak Mac OS X in order to, at least minimize the write amplification problem and also optimize the space used – yes you know the €/MB ratio is high on SSDs. Most of these tweaks, besides providing for a longer lifespan for SSD disks, should improve overall system performance even on an non SSD disk.

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd"> <plist version="1.0"> <dict> <key>Label</key> <string>com.nullvision.noatime</string> <key>ProgramArguments</key> <array> <string>mount</string> <string>-vuwo</string> <string>noatime</string> <string>/</string> </array> <key>RunAtLoad</key> <true/> </dict> </plist>

7 Lessons Learned While Building Reddit to 270 Million Page Views a Month

nice

<p>The 2.6.30 kernel is chock full of next-gen file systems. One such example is NILFS, a new log-structured file system that dramatically improves write performance. </p>

NILFS

"memcachedの特徴は、データをキャッシュするメモリーとして、通常のPCサーバーの物理メモリーを利用すること。大容量データを複数のPCサーバーのメモリーに分散しておくために、「キー・バリュー型データストア」と呼ぶ方法を採用している。データをいったん非正規化し、「キー」とそれに対応する「値（バリュー）」にしてから保存する。データをキーと値の組み合わせにすることで、複数のサーバーに分散しておける。"

Let's come right out with it -- you should be running a dual-band 2.4 and 5GHz WiFi network. Why? Because the 2.4GHz spectrum is cluttered with everything from other networks to Bluetooth to cordless phones and microwaves, and all that RF interference slows everything down, making file transfers interminable and HD streaming nearly impossible. On the other hand, 5GHz 802.11n is clean and incredibly fast -- we're talking almost hardwire fast. But you can't just move up to 5GHz without leaving your phones and other legacy devices behind, so you've got to keep 2.4 around as well -- which is really easy if you've got a simultaneous dual-band router like Apple's new Airport Extreme or something like the D-Link DIR-825, and only slightly harder if you don't. And, as luck would have it, Apple just sent us a new AEBS to play with, so we thought we'd show you how to configure both kinds of setups. We promise you'll thank us.

Let's come right out with it -- you should be running a dual-band 2.4 and 5GHz WiFi network.

a database implementing a dictionary, where every key is associated with a value. every single value has a type. The following types are supported: * Strings * Lists * Sets * Sorted Set (since version 1.1)

maybe the guy is not suitable to address such compare?

Persistent in-memory key value database compared to memcached

tructures and algorithms. Indeed both algorithms and data structures in Redis are properly choosed in order to obtain the best performance.

Flash × テキスト

必要知識

TextFieldの話

いろんな設定検証

comet (and th

Java中性能赶超Erlang的NIO框架。

est was received it either got returned if it had data to return or stored with a timeout (the timeout was adde

The Web Developer's Resource

Your web server should be compressing your files before serving them to your users. Why? There is no reason not to, 99% of browsers know how to decompress them and if you're serious about hosting a professional web site, you should know every second it takes to get your content from your web server to your user counts.

具体的にコードで言うと変数にnullを代入します。

メモリの解放をするには

メモリ解放の手引き

メモリ解放について。

クリック一発でページ内の画像をごっそり最適化

ページの軽さにこだわる人に便利そうなツールのご紹介。smush.itを使えばクリック一発でページ内の画像をごっそり最適化してくれます。 この最適化の処理は、オープンソースの最適化アルゴリズムを活用しつつ、画像が持っているメタデータ（どのエディターで作られたとか）を除去することで実現しているようです。

PHPコーディングに関する最適化TIPS 2009

PHPチューニングの色々。勉強になります。

PHP を使う人は心に留めておきたいですね。

XdebugとWinCacheGrindというソフトを使えばPHPスクリプトのボトルネックを簡単に発見することができます

Network latency and bandwidth are the two metrics most likely to be of interest when you benchmark a network. Even though most service and product advertising focuses on bandwidth, at times the latency can be a more important metric. Here's a look at three projects that include tools to test your network performance: nepim "network pipemeter," LMbench, and nuttcp.

The two most important pieces of advice I can give on speeding up browser scripts, then, are: 1. Never hand-parse a string. 2. Don't do DOM operations in loops (and in general, don't do DOM operations!).

1. Never hand-parse a string. 2. Don't do DOM operations in loops (and in general, don't do DOM operations!).

I like things that go fast, and that includes code that runs fast. With JavaScript (and Java, too), that can be a challenge. So much the better, though. I like challenges too. When someone asks me what's the single best way to speed up "a slow script," naturally I want to know what the script is spending most of its time doing. In browser scripting, it's typical that a "slow" script operation either involves tedious string parsing of some kind, or DOM operations. That's if you don't count programmer-insanity sorts of things, like creating a regular expression object over and over again in a loop.

assertTrue( )

Watch live mysql sql statements with dtrace

helpful

ヨドバシの問題はネットワーク側でなく、やはり CMS の問題みたい

先日CMS導入でトラぶったヨドバシカメラの外側から見た感じ

Magic properties make Firefox synchronously load the Java plugin

"In other words, don't define a window-level function called sun(). It will absolutely kill your page's performance, because at least one modern-day browser will think you want Java, because of a 'feature' invented by Netscape in 1997."

JVM considered harmfull

Browsers are fucked up man. FUCKED UP. Stuff like this makes me smile though.

"Mike Malone shares code used by Pownce to add QuerySet level caching to Django. It’s a smart implementation—a CachingQuerySet class inspects the arguments passed to get(), and if they’re just a straight forward exact PK lookup hits memcache for the object before hitting the database. Signals are used to invalidate the cache."

Some examples of transparently caching things in Django. An example Django app that uses custom managers, fields, and QuerySets to transparently cache objects.

Some examples of transparently caching things in Django.

mmalone's django-caching app

Google code: Page Speed Home http://ow.ly/1TGzV

Page Speed performs several tests on a site's web server configuration and front-end code. These tests are based on a set of best practices known to enhance web page performance. Webmasters who run Page Speed on their pages get a set of scores for each page.

Page Speed is an open-source Firefox/Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them.

Google Page Speed

"Page Speed is an open-source Firefox/Firebug Add-on. Webmasters and web developers can use Page Speed to evaluate the performance of their web pages and to get suggestions on how to improve them."

CSS-Tricks | how efficient is the CSS that we write, in terms of how quickly the browser can render it?

ably decrease load times for a significant chunk of your users just by adding one line of code to your HTML. Pretty cool, huh?

interesante tecnica.

One of the lesser-known jewels of HTML 5 is link prefetching. The idea is to extend the time-honored concept of image preloading to HTML content (and without any messy AJAX code). Here’s how it works: You add a line like this to your page: <link rel="next" href="page2.html"> Then the browser automatically downloads page2.html in a background process as soon as the user’s computer is idle. When the user finally clicks a link to page2.html, the browser serves it from the cache, and so it loads significantly faster. Link prefetching is currently only supported by Firefox. But since Firefox is the second most popular web browser in the world, you can noticeably decrease load times for a significant chunk of your users just by adding one line of code to your HTML. Pretty cool, huh?

Making an iPad HTML5 App & making it really fast

"Images show things down immensely - get rid of them"

これは意外だった。

まじか

セレクタは右から左に解釈される これは正直知らなくて、結構衝撃でした。 #foo .bar {} これはなんとなく#fooを探して、その中の.barを探している気がしてたんですけど、実は.barを探して、その親要素に#fooがあるかを探すそうです。なので特に#fooが必要なければ .bar {} と書いたほうが高速だということ。 また、以下の様に要素名で指定すると、その要素を全て探します。 #foo a {} これは一度a要素を全て探すので、できればaにclassをふって #foo .anchor {} とするほうが高速のようです。（#fooをとるとより高速） 特にユニバーサルセレクタなどは、 #foo * {} とすると、全ての要素の親要素に対して#fooがあるかどうかを調べるので遅くなるようです。

Soluto Is an Awesome Tool to Speed Up Your System Boot & Fix System Slowdowns http://j.mp/bZiE3A

Looks interesting, but comments reveal many problems.

Windows only: Soluto bills itself as an "Anti-Frustration Software", and it's not hard to see why&mdash;it tracks all the applications in your system boot process, and tells you exactly which ones are slowing you down.

536Share Exploring the software behind Facebook, the world’s largest site Posted in Main on June 18th, 2010 by Pingdom FacebookAt the scale that Facebook operates, a lot of traditional approaches to serving web content break down or simply aren’t practical. The challenge for Facebook’s engineers has been to keep the site up and running smoothly in spite of handling close to half a billion active users. This article takes a look at some of the software and techniques they use to accomplish that.

Software Behind Facebook

9 Essential Tips To Speed Up Windows 7: The Microsoft Windows 7 operating system has been designed for delivering ... http://bit.ly/9QxAHy

javascript performance bestpractices development practices ; Forum Nokia Wiki ;

This article gives good and valuable guidance for improving the JavaScript performance in Web Runtime. The article is a collection of guidelines from various sources.

Interesting post about java and concurrency problems, with some nice comments too: http://bit.ly/dtzUL1 – Sergio Bossa (sbtourist) http://twitter.com/sbtourist/statuses/15701705927

270,000

Site speed is one of the most critical company goals for Facebook. In 2009, we successfully made Facebook site twice as fast, which was blogged in this post. Several key innovations from our engineering team made this possible. In this blog post, I will describe one of the secret weapons we used called BigPipe that underlies this great technology achievement.

Pretty cool way of building webpages from facebook to make it super fast.

BigPipe is a fundamental redesign of the dynamic web page serving system. The general idea is to decompose web pages into small chunks called pagelets, and pipeline them through several execution stages inside web servers and browsers. This is similar to the pipelining performed by most modern microprocessors: multiple instructions are pipelined through different execution units of the processor to achieve the best performance. Although BigPipe is a fundamental redesign of the existing web serving process, it does not require changing existing web browsers or servers; it is implemented entirely in PHP and JavaScript.

Site speed is one of the most critical company goals for Facebook. In 2009, we successfully made Facebook site twice as fast, which was blogged in this post. Several key innovations from our engineering team made this possible. In this blog post, I will describe one of the secret weapons we used called BigPipe that underlies this great technology achievement. BigPipe is a fundamental redesign of the dynamic web page serving system. The general idea is to decompose web pages into small chunks called pagelets, and pipeline them through several execution stages inside web servers and browsers. This is similar to the pipelining performed by most modern microprocessors: multiple instructions are pipelined through different execution units of the processor to achieve the best performance. Although BigPipe is a fundamental redesign of the existing web serving process, it does not require changing existing web browsers or servers; it is implemented entirely in PHP and JavaScript.

twice

Medición de rendimiento de sitios web

A tool that helps determine not just response and performance, but helps with client side "perceived" performance. Which can be two different cases.

boomerang is a piece of javascript that you add to your web pages, where it measures the performance of your website from your end user's point of view. It has the ability to send this data back to your server for further analysis. With boomerang, you find out exactly how fast your users think your site is.

Interesting tool allowing measurement of perceived speed of a web site on the client side.

Boomerang measures the performance of your website from your end user's point of view.

JavaScriptコーディング等を書く上でのパフォーマンス確認事項３０:phpspot開発日誌30 best practices to boost your web application performance - Web User Interface Architect JavaScriptコーディング等を書く上でのパフォーマンス確認事項３０。 自分へのインプット＆メモがてらにちょっとま

# 静的なコンテンツはHTTPヘッダでキャッシュさせよう（サーバサイドスクリプトの話） # CSS, JS ファイルはgzipしよう。ただし、（CPU使用率とのバランスは重要です） # JavaScript は　minify して転送量を下げる

JavaScriptコーディング等を書く上でのパフォーマンス確認事項３０:phpspot開発日誌 http://ow.ly/17LULE – Javascript News (del_javascript) http://twitter.com/del_javascript/statuses/16368876741

Bullet / SlimScrooge/ Query Reviewer / Rails Indexes / Ambitious Query Indexer

A few weeks ago I set out to create a new multipart/form-data parser for node.js. We need this parser for the new version of transloadit that we have been working on since our setback last month. The result is a new library called formidable, which, on a high level, makes receiving file uploads with node.js as easy as:

Parsing file uploads at 500 mb/s with node.js » Debuggable Ltd

* Skip to content * Home * Blog * Writing * Speaking * Downloads * About * Contact

SSL is not expensive

"0.1 seconds gives the feeling of instantaneous response... 1 second keeps the user's flow of thought seamless... 10 seconds keeps the user's attention... After 10 seconds, they start thinking about other things..."

Свежий Alertbox от Jakob Nielsen’а. В общем, ничего нового, люди все еще не любят ждать, тем более ждать пока, загрузиться какой-то там сайт.

Website Response Times

Slow page rendering today is typically caused by server delays or overly fancy page widgets, not by big images. Users still hate slow sites and don't hesitate telling us.

0.1 sec 1 sec and 10 sec rules

Quick, what is the fastest way to search a sorted array? Binary search, right? Wrong. There is actually a method called interpolation search, in which, rather than pessimistically looking in the middle of the array, you use a model of the key distribution to predict the location of the key and look there.

Interploating search with alogrithm

http://whichloadsfaster.com <- Try it. Love it. #webdev #velocity

heh

Which loads faster?: A tool for pitting two sites head to head in terms of page speed http://whichloadsfaster.com/ – Jacob Gube (sixrevisions) http://twitter.com/sixrevisions/statuses/18159286709

Comparaisons au niveau de la vitesse de téléchargement

An assessment of mobile brower cache behaviour and recommendations for improving the chances that your content can be cached for improved performance.

An assessment of mobile brower cache behaviour and recommendations for improving the chances that your content can be cached for improved performance.

Ladezeitenoptimierung mit und für jQuery

Solid-state drives (SSDs) have grown popular in recent years for the impressive speed increases your system gains using them. To get the most from your SSD, however, you can (and should) do a few things differently.

One of the best laypersons explanation of algorithm complexity that I've seen.

Traditional computers can solve problems in polynomial time. Certain things are used in the world because of this. Public Key Cryptography is a prime example. It is computationally hard to find two prime factors of a very large number. If it wasn't, we couldn't use the public key systems we use.

Stack Overflow post about Big O notation

Externes Script nachladen, ohne die Hostseite zu bremsen

Load external JS file non-blocking and without delaying onload()

or... How I Increased My WordPress Performance and Got My Page Loads to Under 1 Second.

80% of the time users wait for a web page is because of the frontend. I was sort of thunderstruck with fear. Although we always strive for better, I typically found a 3-5 second page load great and up to 7 seconds acceptable. After recording the show, I stayed up a few hours that night fiddling with The ATX Web Show and increased site performance by ~500%1.

Dave Rupert provides an excellent breakdown of how to speed up your WordPress-powered site. There's no excuse to not spend the time implementing these changes. Even if you're like me, and have already done a lot of the work, I'm willing to bet there's a step or two that will make your site even better. For me, it's the super-duper-easy cut-and-paste improvements to the htacess file to enable gzip and browser caching.

How I Increased My WordPress Performance and Got My Page Loads to Under 1 Second.

boomerang is a piece of javascript that you add to your web pages, where it measures the performance of your website from your end user's point of view. It has the ability to send this data back to your server for further analysis. With boomerang, you find out exactly how fast your users think your site is.

RT @draenews: Del this, is boomerang: http://bit.ly/b08QdK

boomerang - measure performance of your site from your end user's pov - http://bit.ly/dz1vVd

Make Windows leaner, cleaner and faster Speed up your PC with these easy tips : TechRadar UK

tions and wasteful processes are sapping many of your PC's valuable resources. And what's to blame? Windows. Windows is deceptive. After you've installed it, the OS happily connects to the internet, downloads all the necessary drivers, configures itself and there you go – one stable PC all ready to roll. It couldn't be easier or more convenient.

sapping

tions and wasteful processes are sapping many of your PC's valuable resources. And what's to blame? Windows. Windows is deceptive. After you've installed it, the OS happily connects to the internet, downloads all the necessary drivers, configures itself and there you go – one stable PC all ready to roll. It couldn't be easier or more convenient.

sapping

As the inventor of the Judy algorithm I've been asked repeatedly, "What makes Judy so fast?" The answer is not simple, but finally I can share all of the details.

A complex (to implement) but efficient scalable data-structure that obtains very high performance by minimising the number of cache-line fills required.

Buenas practicas para AIR

Now that we have just launched AIR 2, I figured it would be a good time to look back at all the AIR code I've written over the last few months and pick out some of the best snippets and concepts to share with the community. This article describes ten techniques I've used to improve performance, usability, and security of AIR applications, and to make the development process faster and easier.

Tips on optimizing Flash / AIR performance

NovaBench got their nod: http://bit.ly/b0IrZs

As the inventor of the Judy algorithm I've been asked repeatedly, "What makes Judy so fast?" The answer is not simple, but finally I can share all of the details.

A complex (to implement) but efficient scalable data-structure that obtains very high performance by minimising the number of cache-line fills required.