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Firefox stuttering randomly

  • 7 replies
  • 6 have this problem
  • 9 views
  • Last reply by FredMcD

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When I'm randomly scrolling through websites or using tab groups, I can see some stuttering. At start up it's really small and passable, but it gets progressively worse until the window randomly turns black and crashes. I've also noticed that around the time the browser is about to crash, add-ons that are working in the background return a "denied access" entry.

I think it might have something to do with the memory, I usually have 100+ tabs open, but I've the "Don't load tabs until selected" option enabled. Once Firefox hits over 1-1.5 GB it starts stuttering considerably worse. I've also gotten a "out of memory" message before which is why I believe it might be a memory issue.

Anyway, memory usage never gets over 80% of my 8 GB of RAM and I've noticed stuttering on just 50% usage.

Any replies are welcome.

When I'm randomly scrolling through websites or using tab groups, I can see some stuttering. At start up it's really small and passable, but it gets progressively worse until the window randomly turns black and crashes. I've also noticed that around the time the browser is about to crash, add-ons that are working in the background return a "denied access" entry. I think it might have something to do with the memory, I usually have 100+ tabs open, but I've the "Don't load tabs until selected" option enabled. Once Firefox hits over 1-1.5 GB it starts stuttering considerably worse. I've also gotten a "out of memory" message before which is why I believe it might be a memory issue. Anyway, memory usage never gets over 80% of my 8 GB of RAM and I've noticed stuttering on just 50% usage. Any replies are welcome.

All Replies (7)

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We're sorry to hear that Firefox is crashing. In order to assist you better, please follow the steps below to provide us crash IDs to help us learn more about your crash.

  1. Enter about:crashes in the Firefox address bar and press Enter. A Submitted Crash Reports list will appear, similar to the one shown below.
  2. Copy the 5 most recent Report IDs that start with bp- and then go back to your forum question and paste that into the "Post a Reply" box. (Please don't take a screenshot of your crashes, just copy and paste the ID's. The below image is just an example of what your Firefox screen should look like)

aboutcrashesFx29

Thank you for your help!

More information and further troubleshooting steps can be found in the Troubleshoot Firefox crashes (closing or quitting unexpectedly) article.

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I had similar issues. It turned out it was caused by an add-on.

Start Firefox in Safe Mode {web link} While you are in safe mode; Press the Alt or F10 key to bring up the tool bar. Followed by;

Windows; Tools > Options Linux; Edit > Preferences Mac; application name > Preferences

Then Advanced > General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?. Then restart.

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If you still have a problem;

Open your add-ons manager. Disable a few add-ons, then Restart Firefox. If the problem continues, disable some more (restarting FF). Continue until the problem is gone. After, you know what group is causing the issue. Re-enable the last group ONE AT A TIME (restarting FF) until the problem returns.

Once you think you found the problem, disable that and re-enable all the others, then restart again. Let us know who the suspect is detective.

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Firefox on Windows is a 32 bit browser. It will run into memory issues well before using anything like the apparently available 8GB of RAM.

Not sure if the number of reports about stuttering and memory use have been increasing over recent versions of Firefox, certainly subjectively it feels like it is when I read forum questions.

Turn on the telemetry that may help prove the point

I may have some better ideas next week I am having a conversation with HelpDesk staff as to the best method of helping with this sort of issue.


Curiosity & longshot

  • Can you tell from say taskmanager is the stuttering only when Windows OS is using paging memory ?

I am not knowledgeable about Firefox 32bit on 64bit Windows I've transitioned from 32bit Firefox on 32 bit Windows to using 64 bit Firefox on 64bit Linux, and although I do now have 32bit Firefox available on Windows 7 64bit I rarely use it. (Dual boot - not enough RAM for VM)

AFAIK* 33bit Firefox has 4GB virtual address space available on 64 bit Windows compared to 2 or 3GB on 32 bit Windows. If my understanding is correct then maybe Firefox should have no problems with Out Of Memory crashes or severe stuttering at 1-1.5GB of memory use. (I am no expert but Presumably Firefox runs out of address space due to fragmentation etc long before its actual memory usage gets anywhere close to 4GB but should be ok at 1.5GB )

*
(User-mode virtual address space for each 32-bit process 
... x86 ... Up to 3 GB ... Limit in 64-bit Windows ...4 GB with IMAGE_FILE_LARGE_ADDRESS_AWARE set )

Possible memory leak From your description then unless it is just a massive build up of open tabs over time then maybe there is some sort of memory leak. Memory leaks are difficult to troubleshoot and could involve an addon, Firefox or a particular site.

The bad problems where memory shoots up in minutes are easier to troubleshoot and solve than issues where things deteriorate over several days of constant running without a restart.

You mentioned

"At start up it's really small and passable, but it gets progressively worse until ..."
  • What sorts of timescale are involved is it minutes hours or days for instance.

At least now with the built in about:memory tool we can see where the memory is being used by Firefox.

Advance note for next potential step For privacy If you start testing using that and manually submitting results files, use of multiple profiles may be a good idea. That way you can do any sensitive or confidential browsing from a profile that is not used for generating the submitted results.


As Fred mentioned a few very recent submitted Crash IDs may help. Paste in the string including bp-. AFTER preview and posting forum software linkifies them.

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Crash Reports:

bp-82b851f7-c1ad-4f8f-a1e5-fbb7e2140725 24/07/2014 21:26 bp-e727a1b9-9acf-4d9b-90f0-197ff2140724 23/07/2014 21:34 bp-ed9932ed-5507-49da-9d93-57daf2140723 23/07/2014 19:26 bp-5b2fe9f5-f48e-4dd6-a5e3-58ad22140723 23/07/2014 11:39 bp-b1dc9bb8-45c6-41fc-bac2-9d9b42140723 23/07/2014 9:38

I haven't been getting any crashes lately, I used to get crashes at least once every 3+ hours. I created a new profile, imported all the history, and installed every add-on that I originally had. For some reason the crashes have stopped... The stuttering is still there, though. Anyway, I thought this might somehow be relevant. It's not just stuttering, but general unresponsiveness, every time I use tab groups, and change tabs it lags, sometimes up to a good 5+ seconds.

Thanks for the support!

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Nothing jumping out at me, as a solution, from the crash reports, although most will probably relate to memory issues.

As I mentioned in the last post something worth doing is turning on telemetry it generates real life data demonstrating Firefox performance

If you are interested in getting to the bottom of the issue you are probably going to need to start testing in Firefox's safemode with all plugins disabled and less than 30 open tabs.

Possibly the problem only really happens with many tabs open especially with high graphic content

Quite likely stopping memory usage exceeding 1GB or whatever will improve things and I can think of three ways to attempt to reign that in and hopefully prevent the stuttering

  1. Reduce the number of open tabs in use (Maybe use bookmarks more frequently instead of leaving tabs open)
  2. Use about:memory that not only reports on memory it also has a button to reduce memory use.
  3. It could be worth checking out this addon it may help,

For forum cross referencing purposes

  • Reports for your Crash IDs
    1. bp-82b851f7-c1ad-4f8f-a1e5-fbb7e2140725
    2. bp-e727a1b9-9acf-4d9b-90f0-197ff2140724 {Memory 73%)
    3. bp-ed9932ed-5507-49da-9d93-57daf2140723 {Memory 73%)
    4. bp-5b2fe9f5-f48e-4dd6-a5e3-58ad22140723 {OOM but Memory 66%)
  • Crash Signatures:
    1. js::RemapWrapper(JSContext*, JSObject*, JSObject*)
    2. JSC::Yarr::YarrGenerator<int>::opCompileAlternative(JSC::Yarr::PatternAlternative*)
    3. mozilla::layers::PlanarYCbCrImage::GetAsSourceSurface()
    4. OOM | large | mozalloc_abort(char const* const) | mozalloc_handle_oom(unsigned int) | moz_xmalloc | gfxAlphaBoxBlur::Init(gfxRect const&, nsIntSize const&, nsIntSize const&, gfxRect const*, gfxRect
  • Related bugs {with my comments)
    1. Bug 856670 - Firefox crash [@ js::RemapWrapper]
      {Possibly runnning out of stack no STR)
    2. Bug814954 -> Bug 976446 - Replace YARR with irregexp
      { ?Out Of Memory. Fx 32 unaffected)
    3. no related bugs listed
    4. Bug 986502 - Large OOM in gfxAlphaBoxBlur::Init {I added bug comment -- please let me know if you notice this signature in Firefox 31)

Memory issues are not easy to troubleshoot. Stuttering at 50% memory with many addons is going to be impossible to troubleshoot, but 5 second+ lags in normal use is unacceptable. However if that is whilst opening and closing masses of tabs each with their own History and many Iframes and images it my be normal and expected behaviour. (Cacheing, or not; & connection speeds; could be other confounding factors )

If the problem exists in safemode and no plugins enabled it can be followed up and if necessary bugs filed. I am not saying always use Firefox like that just that it is necessary for comparison and troubleshooting to test that. On the other hand If the problem is solved in that configuration you should be able to fairly quickly narrow down the cause.

Using multiple profiles may be useful in testing and I can explain that if it helps. There are tools that may help if you try troubleshooting. I already mentioned about:memory. There is also built a in profiler that will identify what is happening in 5+ second hangs, or a profiler addon that will specifically track and log jank where Firefox stops responding.

Summary I can not guarantee getting to the bottom of your issues but

  • I can at least make suggestions for troubleshooting
  • Problems caused by Firefox rather than by addons will be investigated,
    • and if necessary I am sure the professional HelpDesk staff will be able to lend a hand.
  • Using many addons and hundreds of tabs problems are not unexpected
    • (I hate to say this but on Windows it may be worth trying a 64 bit browser for comparison.
    • However I seem to have noticed; so far unreproducible; issues with High memory usage on recent 64bit Firefox Releases )
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Have you tried disabling your add-ons as I told you above?