CPU usage 100%

[FC360]

I have noticed at times task manager says that cpu usage is 100% however when I double click task manager and sort the process by cpu usage there is no high cpu using processes, and them all added together don't equal anywhere near 100% even if the bottom of the task manager says cpu usage: 100% Why is this?

 

[sminlal]

Click the "View" menu and select "Show kernel times". It may be that you have a rogue device that is constantly interrupting.

 

[FC360]

ok I got the kernel times but no idea what it is or what to look for, so what am I looking for with the kernel times?

 

[sminlal]

Look at the CPU graphs under the "Performance" tab. CPU usage by normal tasks is shown as a green line. CPU usage by the kernel is shown as a red line.

Since you're saying that you've got 100% CPU usage but it's not showing up in any process, I'm guessing that you've got a graph that shows a red line?

If so, your system may be handling an excessive amount of interrupts. One possible cause of this might be a disk that's running in PIO instead of DMA mode.

 

[FC360]

Oh right yeah I got the green line and a red line, the green line is always higher then the red line.

 

[sminlal]

So when the status info at the very bottom of Task Manager says your CPU usage is 100%, does it look like the values for the green line and the red line add up to 100%?

 

[FC360]

yeah it does

 

[sminlal]

OK, so it sounds like you've now been able to account for all of your CPU usage as per your original question.

 

[FC360]

Best answer selected by FC360.

 

[desh2neel]

hello
i m also facing same prob of 100 % cpu usage by some unkown process and my device gettin slower n sounds r cracking wen cpu usage shoot up .......
kindly gimme some solution
ran full antivirus scan but nothin s there ...