Re: PERF: performance tests with the split LRU VM in -mm

From: Rik van Riel
Date: Tue Jul 29 2008 - 09:17:43 EST


On Tue, 29 Jul 2008 22:04:16 +0900
KOSAKI Motohiro <kosaki.motohiro@xxxxxxxxxxxxxx> wrote:

> > TEST 1: dd if=/dev/sda of=/dev/null bs=1M
> >
> > kernel speed swap used
> >
> > 2.6.26 111MB/s 500kB
> > -mm 110MB/s 59MB (ouch, system noticably slower)
> > noforce 111MB/s 128kB
> > stream 108MB/s 0 (slight regression, not sure why yet)
>
> I tried to reproduce it, my ia64 result was
>
> kernel speed swap used
> 2.6.26-rc8 49.8MB/s 1M
> 2.6.26-rc8-mm1 47.6MB/s 168M
> -mm with above two patch 50.2MB/s 0
>
>
> So, I think it isn't regression.

Agreed. It looked like it, but once I changed the cpuspeed
governor from ondemand to performance, I saw that it had to
be an artifact of something else.

Getting rid of the swap use from a linear IO is the important
part.

--
All rights reversed.
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/