100 % CPU usage makes Firefox unusable :-(

[trolly]

This problem indicates that FF has problems accessing the current bookmark file like write protection or insufficient rights. Check your profile folder for read-only files or missing modify right.

[RenegadeX]

Having read all of the previous messages, here's my two cents.

Background:
Two Computers

1) Desktop=500mhz PIII cpu, 384 Ram, 32mb nvidia tnt2 graphics card, XP Home SP2.

2) Laptop=2.8mgz P4, 512mb ddr ram, 96mb shared mem ati rage graphics adapter, XP Home SP2.

3) Website=www.davereillysplace.com using embedded midi file, animated gifs(4), Looping Javascripts(1), Non-looping Javascript(1) and NO Flash content.
<rest snipped..>

Hmm.. tried it on mine - FF1.5RC3 (20051111 .. it never updated AFAIR)

PIII-450 o/c'd to 733mhz, 512MB RAM. Pretty much fast enough for most of my needs.

http://www.davereillysplace.com

- Initial *Firefox* Mem Usage was 131,112K and CPU usage at 0-5% depending on what I was doing in Firefox. Overall CPU Usage % at 10-25%, again depending on what I am doing.
- When the above site loaded, Firefox Mem Usage jumped to 151,000-153,016K (which is what it's at right now as I type).
- Firefox CPU Usage jumped to 81 peak as media files were loading, but constantly changed anywhere from 34% to 73%. Overall CPU % jumping from 50-100%. Embedded music played fine. Watched Task Manager for 20 secs or so and switched back to this tab to start typing.
- After maybe 10 seconds of typing, music started to 'cut out'.. Overall CPU % suddenly maxxed-out to 100%. But Firefox CPU % peak at 86%, momentarily.. and remained in the 71-84%. After 10 seconds or so, music continued to play normally. Overall CPU usage back down to 70-80%, Firefox CPU Usage 40-70%..
- Continued typing here (music stopped now). CPU usage is now 41-45% and Mem Usage remains elevated at 152,852 or thereabouts (/- 2,000K, but never more).
- Reloaded Dave's site in the same tab as before.
- Firefox CPU spiked to 92%, but hovers between 50-70% while music plays. Music plays with no issues now. Overall CPU usage 70-84%.
Scratch that, maybe 30 seconds in... 'stuttering' issue? Nothing abnormal seen in Task Manager besides Firefox, however Overall CPU is 99-100%. Breakup lasts for 5 seconds or so before resuming smoothly. Firefox CPU @ 50-65%, Mem Usage @ 156,312K, Overall CPU @ 56-70%
- reloaded tab again, this time looking at watch to time 'stuttering' of the music. Happens at ~32 seconds. CPU spikes to 100% EVERY TIME.

What is strange about the stuttering issue at about 30secs-in is that after observing this behaviour repeatedly, I decided to watch my network connetion to measure what was coming in. Though I'm on super-fast 9Mbps connection, was it a buffering issue? NO -- between clicking on the page and song end, less than 3,500KB had been received by my system (MSN being the only other app running to require a connection at the time). So why the maxxed out CPU all of a sudden?

[loadbang]

Firefox has always had problems with Flash content using 100% CPU cycles. It has been complained about since Netscape. From what I remember, it's was Macromedia's own problem (now Adobe's).

Windows Media on Mac OS has problems too.

[Abraxias]

my 100% CPU problem, so far, is only with sites that use JavaScript that doesn't work well for my FF 1.5

if I disable JavaScript before viewing the site that causes the 100% CPU problem, it doesn't create the 100% CPU problem but I can't use the JavaScript features of the site (which is sometimes inconvenient). then again, with the 100% CPU problem, I can hardly use the JavaScript features. so, it's just better to keep the JavaScript off on the sites that causes the 100% CPU problem.

[Lost User 183056]

Between July and November of 2005 I spent some time trying to reproduce Bugzilla Bug 251111 with debug trunk builds of Firefox. I am now using a debug build of FireFox 1.5. I have noticed FireFox become unresponsive. My debug window usually looks something like what follows after this comment.

Please note that I see 2 instances of the shockwave flash player being loaded. If I do a quick look at the pages I have loaded, I often times don't see that they have included a "small" window with flash running inside of it. I would like to see some of the folks who develop FLASH stuff create a couple of test cases that we might use to see what is going on here. Unfortunately, I do not do FLASH. However, if we can find a few fairly reliable pages that cause the problem, maybe we can get a FLASH person to create test case for this problem.

Then maybe we could separate performance issues into FLASH related and others. But unless we come out with better ways to reproduce this, we are making it really hard for folks to fix it. So next time Firefox becomes unresponsive, I am going to reboot and try and reproduce the problem, and post my results here.

=====================================================================

For application/x-shockwave-flash found plugin C:\moz\FireFox\dist\bin\plugins\N
PSWF32.dll
JavaScript error: , line 0: uncaught exception: Permission denied to call method
Location.toString
###!!! ASSERTION: XPConnect is being called on a scope without a 'Components' pr
operty!

This is pretty much always bad. It usually means that native code is
making a callback to an interface implemented in JavaScript, but the
document where the JS object was created has already been cleared and the
global properties of that document's window are *gone*. Generally this
indicates a problem that should be addressed in the design and use of the
callback code.
: 'Error', file c:/moz/mozilla/js/src/xpconnect/src/xpcwrappednativescope.cpp, l
ine 564
###!!! ASSERTION: XPConnect is being called on a scope without a 'Components' pr
operty!

For application/x-shockwave-flash found plugin C:\moz\FireFox\dist\bin\plugins\N
PSWF32.dll

[Lost User 183056]

Objective - trying to come up with steps to reproduce showing FireFox CPU usage staying at greater than 70%

My machine
Satellite P35 - Mobile Intel Pentium 4 3.20 GHZ
Total physical memory 512 (448 because of shared video memory)
Microsoft Windows XP Home Edition
Firefox 1.5 - Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8) Gecko/20051201 Firefox/1.5


Observation 1

loading
a) http://blogs.herald.com/dave_barrys_blog/
b) http://mail.google.com/mail/
c) http://www.groklaw.net/
d) http://www.newsforge.com/
e) http://www.npr.org/
f) http://slashdot.org/
g) http://online.wsj.com/public/us


Individually sends my machine to 50% CPU usage with an Explorer and Word window open.
It drops back down to under 5% after the page is fully loaded

Observation 2

Opening all at once (open in tabs) does the same thing but, obviously takes longer to return to normal

This above activity is also enough to have my fan kick in, the fan is nosiy

[norgepaul]

Hi,

I also have the 100% CPU issue and seem to be able to reproduce it. The problem always occurs when I visit: http://www.pspfanboy.com/

The problem seems to be due to the Flash animation (the big one on the right advertising 'smileys'). Try right clicking the Flash ad and changing the quality (low|medium|high) and watch the CPU utilisation change. By disabling plugins for the tab the utilisation drops to 0.

Could this be a bug in the Flash plugin rather than in Firefox itself? If there an alternative?

Cheers,
Paul

[dammad]

This *is* a bug in Firefox, from what I can tell. Unfortunately it's so intermittent (only happens to me every few weeks) I honestly can't pin it down to anything specific.

Flash animations are known to hog the CPU. Did your browsing experience include lots of Flash?

No, not lots of flash (only the one or other ad banner), and no Java or PDFs at all.
It just happens after a random time of surfing.


These are some of the symptoms.

I have pretty much exactly the same problems as the OP; however he is running Firefox on Windows and I am using it on Linux (RH9).

My browser breaks nearly as described above; the differences for me are that the cursor keys and menus do work. I normally notice first of all when the mouse scroll wheel stops working.


Anyway.. rant over.. I assume it's nothing platform-specific as it also affects me on Linux. I also doubt it is Flash specific, as any Flash animation in an open window continues to work as before.. To my untrained mind it seems to be something getting 'stuck' within the browser and preventing things from working / closing.. (Flash apps run *really* slowly on my PC (PIII-500), but that's beside the point and is another question for another day!)

I have found a page that will instantly lock up the cpu at 100%
it's at http://www.abcofcricket.com
it has two flash adds that apear to have nothing but text and opens up two background windows which never seem to load.

[blouwagie]

Hi,

I've read many of the messages in this thread but have not seen anyone make the observation I have:

Win XP, 512 MB, AMD 3000+
- The near 100% CPU usage of FireFox happens quite regularly after resuming from a suspend. I"ll be using FF with several windows open and no real CPU load issues. At night I put PC to sleep ... doing the suspend restart a couple of nights and every now and then my PC will wake up extremely slow... It is almost always FF that eats up all the cycles at that point.
- Most of those times I do not have any flash sites up or sites with flash advertising.
- That bug has existed over several FF iterations... it was there over half a year ago, then seemed to have disappeared, but the latest version 1.0.7 still has it.

Restarting FF and all is OK... That bug is the main reason to still use Opera for 90% of my browsing.. The other being that Opera remembers all my tabs with their sessions even after any crash.

So suspend several nights and FF will start eating many many cycles (sometimes but not all the time).

Thanks
Bart

[nemccurd]

I get the same behaviour. It just happend, in fact, and finally frustrated me enough to come here searching for an answer. My suspicion is that it has something to do with GMail. I don't remember it happening before I switched to GMail. Maybe it's time to try out Opera.

Neil

Hi,

I've read many of the messages in this thread but have not seen anyone make the observation I have:

Win XP, 512 MB, AMD 3000+
- The near 100% CPU usage of FireFox happens quite regularly after resuming from a suspend. I"ll be using FF with several windows open and no real CPU load issues. At night I put PC to sleep ... doing the suspend restart a couple of nights and every now and then my PC will wake up extremely slow... It is almost always FF that eats up all the cycles at that point.
- Most of those times I do not have any flash sites up or sites with flash advertising.
- That bug has existed over several FF iterations... it was there over half a year ago, then seemed to have disappeared, but the latest version 1.0.7 still has it.

Restarting FF and all is OK... That bug is the main reason to still use Opera for 90% of my browsing.. The other being that Opera remembers all my tabs with their sessions even after any crash.

So suspend several nights and FF will start eating many many cycles (sometimes but not all the time).

Thanks
Bart

[madchaz]

I have also been experiencing this issue.

Having gmail opened does not appear to be the triger, as it as occured to me with or without it. However, sites that do frequent reload, like gmail or wired.com, appear to agravate the issue.

I will not always get the issue when I have one such site open, but it occurs more often when I do.

[schapel]

- That bug has existed over several FF iterations... it was there over half a year ago, then seemed to have disappeared, but the latest version 1.0.7 still has it.

Restarting FF and all is OK... That bug is the main reason to still use Opera for 90% of my browsing.. The other being that Opera remembers all my tabs with their sessions even after any crash.

Try <a href="http://www.mozilla.com/">Firefox 1.5.0.1</a> and <a href="http://forums.mozillazine.org/viewtopic.php?t=380534">Session Manager</a>.

Update: I've started the <a href="http://kb.mozillazine.org/Firefox_CPU_usage">Firefox CPU usage</a> article about problems with excessive CPU usage.

[wshtb]

Firefox takes 70-90% CPU after loading www.blogger.com. My system:

Fedora Core 5
Firefox 1.5.0.1
P4-2.8HT
1.5G RAM

[schapel]

Firefox takes 70-90% CPU after loading www.blogger.com. My system:

It seems to be a Linux only bug, because that page consumes 0-1% of CPU on my Windows system. You should discuss this in the Firefox Bugs forum and submit a bug report when you gather as much useful information as you can.

[nezvanova11]

I can be accused of being an extension hog with my FireFox builds {installed/running extensions=35}!
Worse yet >> I actually never stopped installing/using/running TabBrowserExtensions.

Yes! I used to have much bloat with both high CPU usage and high RAM memory footprint with FFv1.5.01 (and all previous version since >> V0.9). My many vain attempts to rectify these problems have never been satisfactory: Even peeling all the way back to running FF in default user mode {-p}, and/or prefetch {/prefetch} enabled, and/or with no extensions installed, did not fully alleviate these woes!

Finally, I am using a combination of the following tweaks to reduce the CPU/RAM usage percentages:
*Installed FlashBlock extension
*Installed FasterFox extension
*Running FireFox in "High Priority" mode {in WinXP OS via orangeProcessTrace program >> but NOT in RealTime}
*Changed PageFile to spread across 4 different SCSI U160 HDDs.

CPU usage has become in the low teens but RAM footprint is still hovering around 90MBytes (but always continues to grow to as high as 150MB).

I am not totally happy but these are numbers I can tolerate to work with (Pentium4/2.4GHz w/1024GB RAM) until a definitive answer is found!