Re: No 100 HZ timer !

[Mark Salisbury <mbs@mc.com>]

On Tue, 10 Apr 2001, Martin Mares wrote:
> Except for machines with very slow timers we really should account time
> to processes during context switch instead of sampling on timer ticks.
> The current values are in many situations (i.e., lots of processes
> or a process frequently waiting for events bound to timer) a pile
> of random numbers.

yup.  however, there is a performance penalty even on fast machines for the
fine grained process time usage accounting, and it in the past there has been a
strong reluctance to add overhead to syscalls and other context switches.

It would probably be a good compile config option to allow fine or coarse
process time accounting, that leaves the choice to the person setting up the
system to make the choice based on their needs.


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