Posted by: felipe | April 30, 2012

Using about:cc to fix leaks

Last week in Toronto, the Firefox team had a work week. One of the activities was a session with lightning talks about various aspects of Firefox development. I gave a lightning talk on how to use Olli’s about:cc add-on to find a leak in the front-end code, understand it and fix it. I tried to emphasize the importance of not creating leaks not only for memory use but also for the browser’s responsiveness, and preparing for it was a good exercise as it helped me learn more how to use it myself.

Here is the video for it, and the awesomely-formatted slides and links are here.

As an alternative, Honza created a similar add-on that uses the same underlying API and has a more user-friendly UI. It’s called about:ccdump and you can find how to use it in his blog post.

Shameless plug:
if you liked the subject and are interested in helping: both about:cc and about:ccdemo uses the cycle collection API to get the cycles data and analyze it. It would be great if this API was also used as part of our testing framework to analyze the data after a test run and help prevent new bugs being introduced. If you would like to work on it, this is filed as bug 728294.



  1. […] Felipe found and fixed memory leaks with about:cc […]

  2. […] Felipe found and fixed memory leaks with about:cc […]


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