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Which tab is using high CPU?

  • 6 replies
  • 1 has this problem
  • 20 views
  • Last reply by cor-el

Shane
Shane
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Greetings,

Firefox is using 100% of my CPU. A yellow banner is displaying at the top saying "A web page is slowing down your browser. What would you like to do?". Windows Task Manager makes it look like there is only one tab in Firefox which is causing the problem. How can I find out which tab is using all my CPU?

Thanks, Shane.

Greetings, Firefox is using 100% of my CPU. A yellow banner is displaying at the top saying "A web page is slowing down your browser. What would you like to do?". Windows Task Manager makes it look like there is only one tab in Firefox which is causing the problem. How can I find out which tab is using all my CPU? Thanks, Shane.

Modified by Shane

All Replies (6)

TyDraniu
TyDraniu
  • Top 25 Contributor
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Jest enter about:performance in the URL bar.

Shane
Shane Question owner
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The Task Manager shows Energy Impact and Memory. How can I add a "CPU" column?

Let me know if you want a Task Manager screenshot.

Thanks, Shane.

jscher2000 - Support Volunteer
jscher2000 - Support Volunteer
  • Top 25 Contributor
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The Windows 10 Task Manager has several panels. Are you using Processes? Right-click any existing column heading to show a list where you can change the set of columns.

Firefox is a multi-process application, but there isn't a one-to-one correspondence between tabs and processes. Each "content" process can contain more than one tab.

Shane
Shane Question owner
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Sorry, when I said Task Manager, I was referring to the one in Firefox. I clicked Menu > More > Task Manager. This opens the about:performance page.

The Windows Task Manager allows me to view a CPU column. Unfortunately, every process is called "Firefox", so I can't find out which tab is causing the problem.

Shane.

cor-el
cor-el
  • Moderator
  • Top 10 Contributor
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See also the about:memory page in addition of about:performance (Firefox Task Manager) (about:about list all available about pages).

cor-el
cor-el
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The Firefox Task Manager shows ordered by the 'energy impact' column what CPU time related (time stamp difference) unless I'm wrong.