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%CPU over 100 in top under linux

Posted on 2007-11-29
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Last Modified: 2013-12-16
Hi,

I'm working on a multithreaded application, in C++, using the ACE framework for TCP and threads.

When used in certain conditions, the application can have up to 400 threads running. All those threads are running a loop with several operations and a sleep of 100 milliseconds.

When used in the worst conditions, top sometimes shows %CPU > 100 (up to 533).
I don't understand this result. Can someone explain how this is possible (how the %CPU is computed to get over 100%) ? Is related to the number of threads ?

Thanks
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Question by:KCTeam
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from_exp earned 125 total points
ID: 20377214
please show me top output and
cat /proc/cpuinfo

I think you have multi processor (or multicore) system
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by:ravenpl
ravenpl earned 125 total points
ID: 20377255
If You have 4 cores(cpus) You can reada 400% CPU time usage. And so on.
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