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High CPU load on idle

  • 3 replies
  • 2 have this problem
  • 7 views
  • Last reply by cor-el

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Hi As soon as I leave a computer and it dims the screen, CPU usage starts to increase. When the screen gets off it starts to consume 100% of one CPU core. If I turn off the screen dimming it does not happen... I have no idea on what's going on there! I tried the safe mode - this does not happen. So I tried to investigate what addon causes it watching about:performance. I found very strange thing - no addon uses cpu heavily but pages start to consume cpu cycles! WTF? How to stop this disturbing FF behaviour?

Hi As soon as I leave a computer and it dims the screen, CPU usage starts to increase. When the screen gets off it starts to consume 100% of one CPU core. If I turn off the screen dimming it does not happen... I have no idea on what's going on there! I tried the safe mode - this does not happen. So I tried to investigate what addon causes it watching about:performance. I found very strange thing - no addon uses cpu heavily but pages start to consume cpu cycles! WTF? How to stop this disturbing FF behaviour?

All Replies (3)

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I did it already as I described in the post.

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If it works in Safe Mode and in normal mode with all extensions ("3-bar" menu button# or Tools -> Add-ons -> Extensions) disabled then try to find which extension is causing the problem by enabling one extension at a time until the problem reappears.

Close and restart Firefox after each change via one of these:

  • "3-bar" menu button# -> Exit (Power button)
  • Windows: File -> Exit
  • Mac: Firefox -> Quit Firefox
  • Linux: File -> Quit

You can try to disable hardware acceleration in Firefox.

  • Options/Preferences -> Advanced -> General -> Browsing: "Use hardware acceleration when available"

You need to close and restart Firefox after toggling this setting.

You can check if there is an update for your graphics display driver and check for hardware acceleration related issues.