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SubjectRe: CPU load

> The kernel looks at what is using cpu _only_ during the
> timer
> interrupt. Which means if your HZ is 1000 it looks at
> what is running
> at precisely the moment those 1000 timer ticks occur. It
> is
> theoretically possible using this measurement system to
> use >99% cpu
> and record 0 usage if you time your cpu usage properly.
> It gets even
> more inaccurate at lower HZ values for the same reason.

I have (had?) code that 'exploits' this. I believe I could eat 90% of cpu
without being noticed.
(cesky, pictures)
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