top, ps etc. lying about cpu idle [was Re: Cyrix 6x86MX and Centaur C6 CPUs in 2.1.102]

Pavel Machek (
Tue, 19 May 1998 10:50:23 +0200


> ...and on an otherwise quiescent system the CPU is quite idle while doing
> a kernel build, specially if you have slow disks like mine, and don't use
> the "make -j" trick. On another VT I could see (using top) that the CPU
> was idle between 15-95%, averaging around 60%.

top is broken broken broken. I can make top see 95% idle while cpu is
running at full tilt, and it happens pretty normally.

TOP is lying about idle time - if you have short-lived processes, top
will not see them (they are gone when it tries to look!) and top
computes idle as 100%-other cpu time, which is broken broken broken.]


The best software in life is free (not shareware)!		Pavel
GCM d? s-: !g p?:+ au- a--@ w+ v- C++@ UL+++ L++ N++ E++ W--- M- Y- R+

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