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Firefox Working to Fix Memory Leaks
Christopher Blanc writes "Many Mozilla community members, including both volunteers and Mozilla Corporation employees, have been
helping to reduce Firefox's memory usage and fix memory leak bugs lately. Hopefully, the result of this effort will be that Firefox 3 uses less memory than Firefox 2 did, especially after it has been used for several hours." Here's hoping. Frequent restarts of things on my computer make me furious. I can't imagine why anyone would tolerate such things.
XUL is inherently single-threaded and JavaScript based. Try out any XUL application out there and you'll see how you get the same poor performance, speed and resource usage as with Firefox (try Miro Player and Joost). ...
Actually I'm pretty sure they're in denial as to the cause of their problems. Announcing they're working on fixing "memory leaks" just supports their ability to continue their delusion.
They're not in denial. They're working on tamarin, a replacement/upgrade of their javascript engine based on the same engine that's in flash 9 / actionscript 3.
Tamarin will run javascript 2, which will to do javascript what the move from actionscript 2 to 3 did for flash/flex. In short: it will make non-toy applications easily done, instead of just marginally feasible. They plan to migrate the firefox UI and extensions to javascript 2, which should negate the performance issues. Only problem: it won't be ready for FF3.
The biggest memory leak does not show up in firefox itself. It shows up in the X process:
:0 -auth /home/me/.serverauth.30245
TIME+ PID USER CODE VIRT SWAP RES SHR S %CPU %MEM P COMMAND
391:42.00 30262 root 1712 864m 481m 383m 5636 R 20.5 38.0 0 X
19:54.97 5473 me 9.9m 350m 202m 148m 18m S 0.0 14.7 0 firefox/firefox-bin
xrestop shows this:
res-base Wins GCs Fnts Pxms Misc Pxm mem Other Total PID Identifier
3600000 295 62 1 2664 119 621592K 12K 621604K ? Firefox Working to Fix Memory Leaks - Mozilla Firefox
In other words, X has over 600MB of memory holding pixmaps for firefox. This grows every time I open a page/tab with images in it.
Closing pages/tabs does not free the memory from X, nor does lowering firefox's various cache settings in the preferences dialog and about:config. Quiting firefox causes X to release the memory. I have to do this at least once a week.
What people call the memory gobbling bug is actually also a CPU hogging bug, and it is still present in Firefox version 2.0.0.7, even though the bug was reported perhaps 5 years ago. Versions 2.0.0.7 and 2.0.0.6 are far more stable than previous versions, but Firefox is still the most unstable program in common use.
The CPU hogging bug in Firefox may be caused by inadequate allocation of resources. Maybe the chaining of the event handler code with numerous windows open is an issue.
Firefox crashes Microsoft Windows. Apparently there is a bug in Windows, or more than one, that causes the entire Microsoft Windows OS to become unstable when Firefox starts CPU hogging. In any case, the only way to get Windows back to a stable state after killing Firefox is to re-start the computer.
It's interesting that Firefox can be used to show that Windows is an unstable OS, in some cases. Linux is completely stable; it is only necessary to kill Firefox to regain resources.
The Firefox CPU hogging bug occurs only during heavy use of Firefox, with many Windows and tabs open for several hours, such as happens when someone in purchasing in a corporate environment is researching computer parts. The problem is made worse if the computer is hibernated or put in standby.
If you open a lot of windows and tabs in Firefox on a laptop, and put the laptop in and out of standby, you will eventually notice that the laptop fan is running all the time, even when there is no activity. That's the CPU bug, and it can potentially shorten the life of your laptop. The fan is often the laptop component that fails first.
It is interesting to note that the latest version of Opera also exhibits CPU hogging, but much less frequently. However, using Opera is not as comfortable because of poor design decisions in Opera.
See: Firefox is the most unstable program in common use.
Firefox developers apparently game the system by abusing those who report bugs: Mozilla Foundation Top 20 Excuses for Not Fixing Firefox Bugs.
Firefox development sometimes resembles playing.
Basically, this seems to be the underlying problem: Winifred Mitchell Baker, the CEO of Mozilla, is a socially uncomfortable lawyer who became CEO when no one thought there was an opportunity. Now Mozilla Foundation is making millions from designating Google as the default search engine.
Winifred has insufficient control over those who work for her, because she doesn't understand what they do. The Firefox CPU hogging and memory gobbling bug would take some serious troubleshooting to find, and no one wants to do the work, apparently.