Firefox 55.0.3 started using >100% CPU.(Mac)

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bluloo
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Joined: November 6th, 2006, 8:13 pm

Firefox 55.0.3 started using >100% CPU.(Mac)

Post by bluloo »

So, after troubleshooting the LastPass addon, by disabling all other addons, then re-enabling them, FF started using more than 100% of the CPU, often becoming almost unusable. Prior to that it was ok, this morning. (Some time ago, it behaved similarly, but an update fixed the problem)

I've currently disabled every addon, except for no script and LP, and I still get the cursor beachball/freezes at regular intervals.
If I check about:performance, it just cycles through random tabs, as slowing down the browser.

I thought tabs were supposed to be unloaded and only load when we clicked on them.
Last edited by DanRaisch on August 29th, 2017, 1:07 pm, edited 1 time in total.
Reason: Added (Mac) to subject line.
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DanRaisch
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Re: Firefox 55.0.3 started using >100% CPU.

Post by DanRaisch »

If no improvement using Safe Mode, do you have the same problem if you create a new profile and test it with no extensions or non-default themes installed?
http://kb.mozillazine.org/Profile_Manager
and
http://kb.mozillazine.org/Creating_a_ne ... on_Windows
bluloo
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Re: Firefox 55.0.3 started using >100% CPU.

Post by bluloo »

Thanks for the reply.

Without creating a new profile, or starting in safe mode:
I'm down to running four extensions. If I restart, using FF's built in session restore, and only open my homepage, and then open a few additional pages, it's mostly fine - usage might spike to 70% but drop to ~ 20% and then to less than 10%. It seems like the number of tabs is the issue. Please correct me if that doesn't appear to be the case.
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DanRaisch
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Re: Firefox 55.0.3 started using >100% CPU.

Post by DanRaisch »

It seems like the number of tabs is the issue. Please correct me if that doesn't appear to be the case.
More tabs require more memory but it will vary by what site is shown in the tabs. Twenty tabs with a static text display may use less memory than one site with multiple concurrent videos running.
bluloo
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Re: Firefox 55.0.3 started using >100% CPU.

Post by bluloo »

DanRaisch wrote:
It seems like the number of tabs is the issue. Please correct me if that doesn't appear to be the case.
More tabs require more memory but it will vary by what site is shown in the tabs. Twenty tabs with a static text display may use less memory than one site with multiple concurrent videos running.
That makes sense.
Does it matter that I only have half a dozen or so active at any one time?

Also, while FF uses quite a bit of memory with lots of tabs present, I've still got ~15GB available, it seems like a CPU issue. I've just reopened my prior session, and the FF is using ~130% CPU. The next closest app is Window Server at less than 5%.

It seems to be the CPU usage causing the regular beachballs and slow-downs in FF.

Also, what seems to be the most confounding to me is that, it only started after I disabled, and then re-enabled, the same set of add-ons this morning - nothing was updated or changed AFAIK. So it was fine with a dozen or so add-ons, I disabled all but one, then re-enabled the set and the CPU hogging and laggy beachballing issue started.
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RobertJ
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by RobertJ »

.
FWIW - On FF 55.0.3 on my Mac I currently have 10 tabs open (No Video) and CPU usage is 4%. with 17 active extensions.

The only time I see a spike in CPU usage is during video or a download. Even then the usage is no higher than 50% when the video is loading and about 20% after it loads and is playing.

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FF 92.0 - TB 78.13 - Mac OSX 10.13.6
bluloo
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by bluloo »

RobertJ wrote:.
FWIW - On FF 55.0.3 on my Mac I currently have 10 tabs open (No Video) and CPU usage is 4%. with 17 active extensions.

The only time I see a spike in CPU usage is during video or a download. Even then the usage is no higher than 50% when the video is loading and about 20% after it loads and is playing.

.
Yeah, it seems to be related to the number of tabs. I can have six or ten tabs open only, and FF is zippy with low CPU usage. I can have 100+ tabs open, and only be actively moving back and forth between 4 of them, and it hogs the CPU and gets very laggy.


The same question remains, why did it start occurring only after the same set of add-ons were re-enabled? Same (large) number of tabs.
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RobertJ
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by RobertJ »

.
I NEVER have more than 6 - 8 tabs open; I only opened 10 to check out your issue.

100+ tabs, WOW, beyond the realm of my experience. :shock:

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FF 92.0 - TB 78.13 - Mac OSX 10.13.6
bluloo
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by bluloo »

So, I did a FF refresh, it re-imported my bookmarks etc, and I then reinstalled 6 extensions so far, and have a hundred tabs+ opened. FF is at ~10% CPU.

Does that mean something was corrupted, and does it indicate what that might have been?

Appreciate the responses, BTW! :)
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DanRaisch
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by DanRaisch »

Does that mean something was corrupted,
Yes.
and does it indicate what that might have been?
No, unfortunately it does not. It could be something as simple as the order in which the extensions are activated during Firefox start up. We've seen instances where just disabling and then re-enabling extensions has resolved issues.
langdonb
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by langdonb »

I have same issues using latest Mac version, 56. Freezes within 2-3 minutes of starting FF, going to 100% CPU usage, 2 -3 tabs open, no flash. Same in Safe mode with hardware access disabled. All this started after upgrading to Sierra, on both an iMac and a new MacBook Pro

On Imac, I had installed a new HDD, so did a clean install of Sierra and all apps, so it was a fresh start. Seems to me it is a Sierra conflict as before that, using Yosemite, did not have theses issues.
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RobertJ
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by RobertJ »

.
I have not seen this. Running Sierra and High Sierra on two different disks on a Pro Mac. I run both FF56 and FF57b with no problem.

In the "clean" install did you start with a new FF profile since that is where all the important FF things are located.

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FF 92.0 - TB 78.13 - Mac OSX 10.13.6
langdonb
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by langdonb »

No new profile, not sure how to do that. I am running FF on my laptop and used the same account for the iMac for synching purposes. just now, I deleted the iMac's FF using Appcleaner which I believe deleted anything related to FF. And now I am going to try synching to get my bookmarks and passwords back. Should I not use my current FF account name, etc??
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RobertJ
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by RobertJ »

.
I don't know what FF sync actually does. Look here

/Users/<acct>/Library/Application Support/Firefox

to see if there are existing profiles. Post back what you find. I will be around for about 45 min and again Sunday about 1:00 PM your time.

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FF 92.0 - TB 78.13 - Mac OSX 10.13.6
langdonb
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Re: Firefox 55.0.3 started using >100% CPU.(Mac)

Post by langdonb »

BTW, I run FF on my laptop using "portable Firefox". So I deleted that app and reloaded with a version on my back up from a month ago and it seems to be running OK...

I do want to move forward with installing a fresh version on the iMac and be able to synch with the laptop,,,
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