Devit!

Google recently rolled out Page Speed, an open-source Firefox/Firebug extension, allowing you to evaluate a site’s performance.

This immediately warrants a comparison to Yahoo’s YSlow Firebug extension, which has been out for almost two years.

YSlow has been very useful around here, so Page Speed has to not only meet that usefulness, but also exceed it to warrant switching which tool we use for site tuning.

Spoiler alert: YSlow wins!

YSlow Likes

YSlow has a really cool compiler that puts all loaded Javascript into one file. It can also do the same for CSS. Just choose Tools|All JS and Tools|All CSS.

Information about each suggestion under Performance, when clicked, pops up in a new Firefox tab.  The information about every suggestion is all in one page, and you are anchored to the item you chose.

The Stats page shows the size of your page with an empty cache, and compares it to the size when cached.

YSlow Dislikes

Our only gripe with YSlow is that it doesn’t do as many checks as Page Speed.  We would like to see suggestions of efficient CSS selectors.

Speed Likes

At first look the Page Speed Activity monitor seemed really helpful. It shows the length of all requests, including images loading and ajax calls.

Page Speed has more thorough checks than YSlow. Running both tools on the same page, Page Speed tells you to combine external Javascript and CSS files, remove unused CSS, and use more efficient CSS selectors.

Page Speed Dislikes

Page Speed is off to a great start, but there are some things that we don’t like about it.

Clicking on a suggestion brings up the information page in a new window.  YSlow’s info pages open in a new tab, where you can still see your original site and go back to it without closing the new page. We’d like to see Page Speed take advantage of Firefox’s tabbed browsing!

The Page Speed Activity monitor is quite buggy, and a has crashed our browsers multiple times. Sometimes the Activity monitor itself crashes, and the only way you can get back to it is by restarting the browser.

Conclusion

Google’s Page Speed is in its first version, while YSlow has been around long enough to be a little more polished. For now, we’re sticking with YSlow, but won’t hesitate to try the next iteration of Page Speed.

Don’t worry, Google – Page Speed still wins this fight!

What about you? Which performance tuning Firebug extension do you prefer, and why?

gavinblair

As someone who loves to help others, Gavin is not easily ruffled. Poorly designed software is one of his few pet peeves, and we can count on Gavin to find solutions and make improvements in all kinds of applications. In his own words, he likes to "fight the good fight for quality code." He loves food and finding adventure in the kitchen, cooking with his wife. On one occasion, the combination of a white-hot skillet and no ventilation led to so much smoke they had to stop, drop and roll - but did end up eating "the best blackened catfish po'boy you can imagine."

This entry was posted on Wednesday, July 22nd, 2009 at 2:38 pm and is filed under Devit!. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.