A hodge-podge of things happened this week.
- The Mozilla QA team started running MozMill endurance tests every day. This should help identify and avoid regressions in memory usage in the future.
- Mihai Sucan fixed some memory leaks in the web console.
- Joe Siegrist, author of the LastPass add-on, fixed a leak in it that was causing zombie compartments. This fix is in version 1.75.0.
- Justin Lebar fixed a problem in the image memory reporters that could cause nonsensical results (such as negative numbers) in about:memory.
- Igor Bukanov added memory reporters to distinguish between clean and dirty unused chunk memory in about:memory.
- Sander van Veen, a new Mozilla contributor, wrote patches for two MemShrink bugs: bug 673737 and bug 673331. I’ll land the first one soon, and the second one is waiting for a review. Great work, Sander!
- I wrote about some allocations that are wasting space, and quantified Firefox 7′s memory usage improvements. The latter post’s take-home message was that “Firefox 7 uses less memory than Firefox 6 (and 5 and 4): often 20% to 30% less, and sometimes as much as 50% less.”
The MemShrink bug counts changed as follows.
- P1: 29 (-2, +4)
- P2: 62 (-5, +14)
- P3: 41 (-0, +6)
- Unprioritized: 2 (-10, +1)
We actually got through almost all the unprioritized bugs in today’s MemShrink meeting, which was good, but the counts are still going up. Fortunately, most of the new bugs are ideas for improvement that are reported by developers. My gut feeling (which I get from reading a lot of memory-related bug reports) is that the number of reports from users about high memory usage are much lower than they were a few months ago.