Processor Utilization

Question

Out of curiosity ... is it possible to have more than 100% utilization of the CPU in a multi-threaded environment?

score 5 · Answer 1 · edited Oct 10 '12 at 16:35

5

No, of course not. And any utility which tells you otherwise is lying.

edited Oct 10 '12 at 16:35

user229044

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answered Feb 01 '10 at 14:52

High Performance Mark

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@David, you need to keep your finger on the trigger a bit longerrrrrrrrrrrrrrrrr :-) – High Performance Mark Feb 01 '10 at 14:56

score 3 · Answer 2 · answered Feb 01 '10 at 14:55

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a single CPU core can not be at more than 100% utilization. But on a multi core system most utilities report the sum of the CPU utilization thus numbers above 100% are quite common.

answered Feb 01 '10 at 14:55

Gareth Davis

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True. `top` can show more than 100% for a multithreaded application – Feb 01 '10 at 15:01

score 0 · Answer 3 · answered Feb 01 '10 at 14:54

No, this could never happen by definition of cpu utilization. What you may see is the number of runnable processes greater than the number of cpus. This is normal in a multithreaded environment as the scheduler schedules on the thread level instaed of the process level.

Processor Utilization

3 Answers3