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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.
I don't mind the memory. I have plenty of gigs even in my laptop. What I mind is the general slowness that I experience with Firefox, and that makes me use Opera on my laptop even though I would feel better using an open source browser.
c++;
Nobody forces you to use Firefox. You can use Opera, Konqueror, links or IE, or any other browser out there...
Ok.
Well, it has never been successfully tested.
Actually, from what I understood over the last year "THERE IS NO MEMORY PROBLEM".
Every time someone mentions memory issues, the responses are either that it's supposed to consume a gigabyte of ram so that it speeds up the back button or that "there is no memory issue".
Strange, now, that there are suddenly people paying attention to specifically attacking memory use issues that supposedly don't exist.
If you can't code without hand-holding tools like automatic garbage collection, perhaps you belong in a different profession!
Firefox's problem is architectural and not one of garbage collection.
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).
The Firefox developers are literally throwing out more C code with every release, replacing it with JavaScript code.
Leaks (in the classical sense) aren't what's causing Firefox's abysmal performance, and this is why Firefox 2 performs worse than Firefox 1.5, despite one of the "features" of Firefox 2 was supposedly plenty of fixed memory leaks.
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.
C/C++ and similar languages, on the other hand, force the programmers to manage their resources. In those cases, the programmers would likely be just not designing their programs well, or employing bad resource management. Yes, managing resources can be hard - one project I worked on had to go through several months of testing to get the resources properly managed, and even then some of the resources were still a little uncontrollable due to legacy code or Windows APIs, but overall the thing was pretty stable and any memory leaks were mostly due to Windows APIs.
In either case, I can't tell you how many times I have heard (especially from Java programmers) something along the lines of the following: "RAM is cheap", "processors are getting faster", "computers will be ready for this when we deliver it", "hardware is cheaper than programmers"
No offense, but to rely on hardware always being getting faster, or the cost of adding more RAM always being cheaper, etc. is a bad premise to rely on. Already with multi-core processors we are seeing slower processors being combined into a single processor get the equivalent processing power of a faster processor (e.g. two 1.8 Ghz cores rated equally to a single 3 Ghz core); thus the premise breaks down. Also, I want to be able to do more with the faster processors and additional RAM, rather than simply do the same job I could do yesterday only in "better" software.
The real answer is doing your job right, and using the right tool - which is not necessarily the easiest tool to use either. We also need to get back to writing applications that have good, if not great, performance with minimal resource requirements (e.g. RAM and processor). If we're not going this at the API/library level - at the very least - then the programs and library/APIs that rely on that API/library level will have worse performance no matter what they do. But in either case it doesn't get done unless the programmers do their job, and use tools that allow them to do it.
Truth is like the sun. You can shut it out for a time, but it ain't goin' away. - Elvis Presley (source: imdb.com)
1. Custom malloc/free implementation. (Yes, custom - not from libc.)
2. C++ new/delete operators, which for all I know may be overridden to use their malloc/free.
3. One of the first two with reference counting to decide when to free/delete.
4. JavaScript mark-and-sweep GC.
Dealing with this causes some truly insane hacks, like the absolutely insane DOM C++/JavaScript implementation. (They're C++ objects, exposed as JavaScript objects, using something that's like XPCOM but isn't due to the overhead XPCOM imposes. I really don't understand it.)
Ultimately, though, it's worse than all that. All this crap leaves the code completely opaque, and actively prevents contributors from contributing code without having to learn an insane amount of infrastructure decisions.
It makes a project that's supposed to be open source effectively closed off to only the "official" developers: almost open source in name only.
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.