Stuart Parmenter has been blogging about his work on memory usage and various malloc() libraries and their tradeoffs.
In his latest, he talks about the memory usage in Firefox 3 today and the work that he has done:
What about the tests?
For the results below we loaded 29 different web pages through 30 windows over 11 cycles (319 total page loads), always opening a new window for each page load (closing the oldest window alive once we hit 30 windows). At the end we close all the windows but one and let the browser sit for a few minutes so see if they will reclaim memory, clear short-term caches, etc. There is a 3 second delay between page loads to try and get all the browsers to take the same amount of time.

Great work guys, and thanks for talking to us about how you are doing this work!
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