Firefox 7 and Browser Memory Consumption
Firefox 7 uses less memory than Firefox 6 (and 5 and 4): often 20% to 30% less, and sometimes as much as 50% less. In particular, Firefox 7?s memory usage will stay steady if you leave it running overnight, and it will free up more memory when you close many tabs.
This sounds like real progress even if the figures cited seem a bit overblown, based as they are on an artificial scenario (opening 150 browser windows on a machine with 16Gb of RAM). Web pages take up RAM mainly because their in-memory representation (DOM) is large. Browsers with a lot of pages open unavoidably use a lot of memory (and I can attest personally that Chrome is no exception). It therefore makes sense to focus on areas where big improvements can be made, like freeing memory more quickly when pages are closed. Don’t expect memory usage to halve during real world usage, but it should improve significantly if you open and close pages a lot (and who doesn’t?).
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