This blog..

.. is about optimisation that isn't evil.

Defer the loading of 3rd party addons

I just discovered the informative blog-post “Optimize the Performance of Widgets, Buttons & More” on

It’s a well known problem that 3rd-party services included in a web page can become a performance bottleneck.

The article explains how to defer the loading of 3rd-party widgets (like google ads, social network plugins etc.) until after the HTML is rendered. It gives a lot of code examples for the most popular addons (also for some that I didn’t hear of). These should enable you to add the JS functionality after the page has been loaded for these elements.

W3C Launches Web Performance Interest Group

On the 8th of February, W3C announced the launch of a Web Performance Interest Group:

Today W3C launches a new Web Performance Interest Group, whose mission is to create a faster user experience on the Web. The Interest Group will produce use cases and requirements for future deliverables of the Web Performance Working Group. [..]

Hopefully, that will result in a bunch of standards to speed up the web!

There’s also a public mailinglist for those of you that like to take part in the discussion.

52 interesting Blogposts on web application performance

On the Dynatrace Blog a nice summary of their web application performance blog posts has been posted:
52 weeks of Application Performance – The dynaTrace Almanac

Take a look, they cover a wide range of problems with examples, from frontend to backend over management themes:

We hope that there are topics for everybody. The articles range from technical to conceptual areas of performance management.  They reflect what took our attention throughout the year. We hope that you enjoy reading them.

Of course, if you’re following the latest trends in web application performance or have been interested in it for a while, some of the articles don’t really have new information.

Faster webpages with mod_pagespeed

Google announced mod_pagespeed, a module for Apache that changes the content to automatically follow a lot of well-known web application performance optimization guidelines. At the documentation, the available filters are explained in detail. Bonus: There’s also a section in the documentation about the potential risks of every filter.

Continue reading Faster webpages with mod_pagespeed

Better performance requirements

A task with performance engineering that’s often encountered is to define requirements for performance. This is a task that isn’t easy to accomplish, especially if you start from scratch.
On the SearchSoftwareQuality-Blog, a helpful article has been posted: Seven quick tips for better performance requirements
Continue reading Better performance requirements

Theory of performance tuning

I stumbled across a nice article at titled “Thinking Clearly about Performance“.
Continue reading Theory of performance tuning

Improving speed of https pages

When it comes to secure sites, it’s not easy to achieve a fast loading page.

There are a few points that really help:
Continue reading Improving speed of https pages

Why good web app performance rocks

In this article, Steve talks about the impacts (he has commulated some interesting numbers from other blogs) and recent trends in the web app performance industry.

He also references a video from a Fred Wilson (a NY tech investor) speech. Guess what: From the “10 Golden Principles of Successful Web Apps”, in his opinion performance is number one.

The most fun part of his article definetly is:

Netflix – Adopting a single optimization, gzip compression, resulted in a 13-25% speedup and cut their outbound network traffic by 50%.

Guys, please read Performance First Aid: Basics! Using compression is the norm for like … 10 years?

Velocity 2010

Velocity 2010, Web Performance & Operations Conference is just over.

The slides for some of the talks already are available online. Some of the web performance talks are quite interesting:
Continue reading Velocity 2010

yum install iostat

Sometimes you’re working on a machine and miss a certain tool. In my case, it was iostat I missed on a Red Hat server. iostat is a useful tool for a quick look at the I/O statistics of a unix/linux based machine.
Continue reading yum install iostat