Re: inlines in kernel/sched.c

[Rik van Riel]

On Sun, 28 Jul 2002, Ingo Molnar wrote:
> On Sun, 28 Jul 2002, Andrew Morton wrote:
>
> > Ingo, could you please review the use of inlines in the
> > scheduler sometime?  They seem to be excessive.
> >
> > For example, this patch reduces the sched.d icache footprint
> > by 1.5 kilobytes.
>
> the patch also hurts context-switch latencies - it went
> from 1.35 usecs to 1.42 usecs - a 5% drop.

That's 140 cpu cycles on a 2 GHz CPU, probably less time than
what a single cache miss would cost for non-scheduler-intensive
workloads.

This would mean that for a workload which is doing real work,
and pushes the scheduler out of the L1 cache, the slowdown
would be a lot more simply due to the extra cache misses the
extra inlines generate.

regards,

Rik
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