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Why does Firfox use so much CPU compared to other browsers and how may I prevent high CPU usage?

  • 5 replies
  • 3 have this problem
  • 4 views
  • Last reply by James

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I've noticed that recently Firefox had been using WAY too much of my CPU while I was watching livestreams on twitch.tv. So I upgraded to the most recent version of Firefox to see if that would fix it. This made it worse. Now it's plugincontainerforfirefox that's taking so much CPU. I've played these streams in internet explorer and Google Chrome and both use less than 15% of my CPU while Firefox is taking a whopping 45%. So I decided to upgrade to Windows 10 to see if that would fix it somehow. It did not change the issue at all. I've tried disabling hardware acceleration and that made no change (so I switched it back on). I've tried typing about:config and filtering for "dom.ipc.plugins.enabled" and setting it from true to false and that has not fixed it. I love me my Firefox and don't want to switch to using Chrome or Microsoft Edge. I'm not sure if this is a common bug that needs fixing on Mozilla's end or if it's just bad luck for me :(


irrelevant note: I also have to restart Firefox periodically (I'd say about once every other hour) because it will act like I have no internet when I do. Restarting fixes this temporarily.

I've noticed that recently Firefox had been using WAY too much of my CPU while I was watching livestreams on twitch.tv. So I upgraded to the most recent version of Firefox to see if that would fix it. This made it worse. Now it's plugincontainerforfirefox that's taking so much CPU. I've played these streams in internet explorer and Google Chrome and both use less than 15% of my CPU while Firefox is taking a whopping 45%. So I decided to upgrade to Windows 10 to see if that would fix it somehow. It did not change the issue at all. I've tried disabling hardware acceleration and that made no change (so I switched it back on). I've tried typing about:config and filtering for "dom.ipc.plugins.enabled" and setting it from true to false and that has not fixed it. I love me my Firefox and don't want to switch to using Chrome or Microsoft Edge. I'm not sure if this is a common bug that needs fixing on Mozilla's end or if it's just bad luck for me :( irrelevant note: I also have to restart Firefox periodically (I'd say about once every other hour) because it will act like I have no internet when I do. Restarting fixes this temporarily.

All Replies (5)

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I believe streaming always slows down the CPU, on mine it does. Here is what helped me. My CPU is not very fast, but with the setup I have with my Firefox, its made it a tiny bit faster than Chrome: 1. Download the Fasterfox add-on. This helps Firefox speed issues. This is a great add-on as this does not bother you at all, it just does it thing quietly.

2. Type about:config in the address bar < click "I'll be careful I promise!" < In the search bar, type "network.http.version". Make sure it's set to 1.1. < Now type "pipeline" in the search bar. Look for network.http.pipelining. Double-click on it to set it to "true" in the Value column. < Look for "network.http.proxy.pipelining" and double-click on it to set it to "true". < Now look for "network.http.pipelining.maxrequests", double-click and set the value to 8, but if you notice the internet doing weird things, change the number to 7 or 6 or lower.

Hope that helps, it may not have solved the CPU issues, but with a faster Firefox, it should help some. Let us know if this solves your problem!

Modified by user158825061702048981161559993040890724972

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Firefox uses a npapi version of Flash player plugin. Chrome comes with a Pepper Flash player or PPAPI and Edge uses its own Flash Player. So the browsers do not use the same Flash plugin.

Sometime in 2016 Twitch plans to have HTML5 for the video part also and not just controls and chat.

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Sauceman said

look for "network.http.pipelining.maxrequests", double-click and set the value to 8, but if you notice the internet doing weird things, change the number to 7 or 6 or lower.

network.http.pipelining.maxrequests has had a default increase from 4 to 32 since Firefox 14.0

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I do not trust the internet, but from my research on this, according to people, they say to increase the number for 4 to 32, but according to some tech websites they said it doesn't matter, leave it at 8. One website has said this:

"Most blogs you read are going to tell you to set the “network.http.pipelining.maxrequests” value to some huge number like 30, so you can make 30 http requests at once. This is why that’s ridiculous:

   Firefox only has the ability to send 8 requests at once, so altering this value to anything higher than 8 is pointless. Will it hurt anything if you set it that high? No, but it just shows you that the people who told you to do this don’t know what they’re doing.
   Even if it could send 30 http requests at once, you wouldn’t want to set it that high. If everyone made 30 simultaneous http requests to every web server they connected with, the internet would be slow, webmasters would hate you (and Mozilla,) and your IP would probably be banned from many websites. There is a reason that this setting is turned off by default.
   The higher you set this value, the more likely it is that you will break something. But don’t fret about it."

Now James, if the default for Firefox is now set to 32, does that mean Firefox increased the ability to perform 32 tasks at once? I hope so, but I don't know, if so then I will change my original post and update my Firefox settings then. Let me know

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When the default was 4 it was during when it was hard capped at 8 max no matter the higher number suggested by so called make Firefox faster tips copy and pasted all around then. I believe there is no upper limit cap now since Firefox 14.0.