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If anyone has a single site or small sequence of sites that can can be reloaded repeatedly to reproduce this issue (say... memory usage over 300MB. over 100MB is normal and expected), please let me know. The main problem with almost all the bug reports filed to date on memory usage is they're basically "just browse around for a day or two and you'll see it".

The few with specific instructions to reproduce the issue have definitely gotten a good response. For example, all of the following improvements resulted from testing on Mozilla's MemBuster set of pages:

http://trac.webkit.org/changeset/38679
http://trac.webkit.org/changeset/38635
http://trac.webkit.org/changeset/38407
http://trac.webkit.org/changeset/38298
http://trac.webkit.org/changeset/38296
http://trac.webkit.org/changeset/38285
http://trac.webkit.org/changeset/37508

http://trac.webkit.org/changeset/28006 is another example from a different test page.
 
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