Re: [patch] voluntary-preempt-2.6.8.1-P5

From: Ingo Molnar
Date: Sat Aug 21 2004 - 04:15:19 EST



* Lee Revell <rlrevell@xxxxxxxxxxx> wrote:

> On Fri, 2004-08-20 at 09:30, Ingo Molnar wrote:
>
> > - reduce ZAP_BLOCK_SIZE to 16 when vp != 0. This pushes the exit
> > latency down to below 100 usecs on Lee Revell's box.
> >
>
> Almost:
>
> http://krustophenia.net/testresults.php?dataset=2.6.8.1-P6#/var/www/2.6.8.1-P6/trace8.txt

i suspect if you turn off tracing (or disable it in the kernel
completely) then you'd see below-100 usec latencies here. A trace entry
costs ~0.3 usecs on your box, so this 50-entry trace has roughly 15
usecs of tracing overhead :-)

Ingo
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