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Firefox 58 and high CPU/Heat

  • 9 replies
  • 4 have this problem
  • 2 views
  • Last reply by Timtak

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Basic browsing within FF causes my CPU and GPU usage to skyrocket (in FF 58.0.2 and macOS 10.13.3) and has been like this since the release of FF 57. I've tried multiple "refreshes" of the browser, changed my performance settings, disabled add-ons, and even tried wiping and reinstalling my entire operating system in an effort to chase down whatever is causing these excessive CPU cycles and heat generation--but after each attempt on my end to alleviate the issue, FF still runs hot.

I want to use Firefox. I want to believe it's the best web browser for me (despite what machine I'm using, I have ALWAYS had the latest version of FF installed and ready to go since the v2) However the excessive CPU cycles and general added heat this adds to my machine (15" mid-2015 MacBook Pro 2.2GHz/16GB RAM) is just plain astonishing and pushing me away.

Other browsers that I've used don't use nearly as much CPU -- under normal circumstances, my daily browsing within Safari and Chrome keep my CPU and GPU around 35-45°C -- whereas the same browsing habits and OS conditions while using Firefox consistently keep my CPU & GPU between 55-80°C -- which for a release (quantum) that claims to be better performing and resource friendly is shameful.

Is this a Mac problem..? Are other people not experiencing this?

I've done everything on my end that I can think of to reduce the processor cycles and heat build up by Firefox--but I have to say, Chrome and Safari out of the box don't require any such tweaking to make them run cool--which for a browser that's backed by a company attempting to make the claim it's the fastest and resource friendly browser out there is again, astonishing.

Has anyone else experienced this..

Basic browsing within FF causes my CPU and GPU usage to skyrocket (in FF 58.0.2 and macOS 10.13.3) and has been like this since the release of FF 57. I've tried multiple "refreshes" of the browser, changed my performance settings, disabled add-ons, and even tried wiping and reinstalling my entire operating system in an effort to chase down whatever is causing these excessive CPU cycles and heat generation--but after each attempt on my end to alleviate the issue, FF still runs hot. I want to use Firefox. I want to believe it's the best web browser for me (despite what machine I'm using, I have ALWAYS had the latest version of FF installed and ready to go since the v2) However the excessive CPU cycles and general added heat this adds to my machine (15" mid-2015 MacBook Pro 2.2GHz/16GB RAM) is just plain astonishing and pushing me away. Other browsers that I've used don't use nearly as much CPU -- under normal circumstances, my daily browsing within Safari and Chrome keep my CPU and GPU around 35-45°C -- whereas the same browsing habits and OS conditions while using Firefox consistently keep my CPU & GPU between 55-80°C -- which for a release (quantum) that claims to be better performing and resource friendly is shameful. Is this a Mac problem..? Are other people not experiencing this? I've done everything on my end that I can think of to reduce the processor cycles and heat build up by Firefox--but I have to say, Chrome and Safari out of the box don't require any such tweaking to make them run cool--which for a browser that's backed by a company attempting to make the claim it's the fastest and resource friendly browser out there is again, astonishing. Has anyone else experienced this..

All Replies (9)

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Yes, this is probably a Mac issue. There are reports, that this is fixed in version 60.

https://twitter.com/NorbertDragan/status/955570320718655489 https://bugzilla.mozilla.org/show_bug.cgi?id=1432359

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Unfortunately, the most recent nightly (as of 13.02.2018) did not alleviate the high CPU/excess heat for me on my machine. I'm not going to scorn Mozilla for having trouble with this -- I guess if all we (as Mac users) cared about was system resource and heat, we would stay with Safari - but it still feels like FF on Mac is a second class citizen...

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I'm having the same issue. My CPU load is way too high, already with only one tab open. I also get temps around 70-80°C.

I'm however running Firefox 58.0.1 on Fedora 27.

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My issue with the whole application (Firefox) isn't necessarily the simple fact that it uses high amounts of CPU and generates heat.. it's that when I compare it to other browsers on my machine--specifically Chrome..as it's traditionally known on mac as a serious resource hog--Firefox doesn't run just a little hotter, or use just a little more CPU - it uses A LOT MORE CPU and even RAM than when compared to chrome-- (both in the latest releases..)

It would be unfair for me to compare this to Safari -- Apple clearly has the advantage here; with them being able to code a proprietary, locked down browser for the same in house, proprietary locked down operating system -- but again, chrome (although proprietary, and mostly locked down) is a seriously polite (LOW cpu/ LOW heat) application on my system

I would just like to see Firefox compare similarly to chrome in this field.

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Can you turn off hardware acceleration (multiprocessing) in Options? That seems to have really stabilised things for me on Windows 7. The big advantage of 57 is the speed achieved by multiprocessing but at the same time it is a big load and my browsing on pre-Quantum FF was fast enough.

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timtak said

Can you turn off hardware acceleration (multiprocessing) in Options? That seems to have really stabilised things for me on Windows 7. The big advantage of 57 is the speed achieved by multiprocessing but at the same time it is a big load and my browsing on pre-Quantum FF was fast enough.

unfortunately, turning off hardware acceleration on my machine makes the heat worse -- that was one of the very first things I tried when I noticed the excess heat -- I figured that perhaps the new firefox build/engine was poorly optimized for my graphics card, but it turned out to make it worse.

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scott fitch said

unfortunately, turning off hardware acceleration on my machine makes the heat worse -- that was one of the very first things I tried when I noticed the excess heat -- I figured that perhaps the new firefox build/engine was poorly optimized for my graphics card, but it turned out to make it worse.

Ah, that's a shame, but by the way, on my Windows machine the hardware acceleration refers to multiprocessor use not, it would seem, graphics card use. But then perhaps graphics card use is not mentioned. I used to get blue screens of death due to inter processor communication timing out, but turning off this multiprocessing capability seems to have cured things.

Please see the attached image.

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I'll give it another try--at this point I'm willing to duplicate my previous efforts in an attempt to get Firefox to be a little more respectable.

Again, if it were a video editing software, I can abide and completely understand pegging my CPU and GPU like it does--that kind of software obviously needs that sort of power...but this heat generation really bothers me..I look at excess heat in my MacBook Pro like a mechanic would see a car consistently running too hot--it may not harm you day-to-day, but in the long run it isn't good for your car--and I don't want to have to buy another MacBook anytime soon...I like to get the most out of my investment. So until this issue calms down, I'll stick with Chrome (maybe safari..it seems Chrome is running cooler than safari these days anyway..)

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Quantum is really into multiprocessing. This means that it is very fast but also that there is a lot of interprocessor communication. My computer (Win7) would always be working hard when using 57+ Firefox. I switched to Chrome too but I now find FF 58 to be okay (probably as slow as 56 which was quite fast enough for me) if I turn off multiprocessing in the Options.