Date: Mon, 19 Jul 2004 11:56:06 -0400 (EDT) From: Robert Watson <rwatson@FreeBSD.org> To: John Baldwin <jhb@FreeBSD.org> Cc: Eric Anderson <anderson@centtech.com> Subject: thread+preemption stability improvement (was: Re: ACPI degrading.. ?) Message-ID: <Pine.NEB.3.96L.1040719115338.38770K-100000@fledge.watson.org> In-Reply-To: <200406301118.33680.jhb@FreeBSD.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Wed, 30 Jun 2004, John Baldwin wrote:
> Try this patch. It fixed all my lockups with xmms in KDE on Friday:
This patch causes my SMP and UP tests to succeed with PREEMPTION enabled,
whereas before they rapidly hung. On SMP I see a small (just under 1%)
but consistent improvement in query throughput with MySQL, and on UP I see
a small (just under 1%) but inconsistent decrease in query throughput with
MySQL. The standard deviation on the UP case is almost the same size as
the change, but in the SMP case it's 1/4-1/3 the size of the change, FWIW.
Can't speak to the latency as the test I'm currently running isn't very
latency sensitive, but was very sensitive to the stability issue. I think
this patch is definitely worth committing ASAP :-).
Robert N M Watson FreeBSD Core Team, TrustedBSD Projects
robert@fledge.watson.org Principal Research Scientist, McAfee Research
>
> --- //depot/projects/smpng/sys/i386/i386/intr_machdep.c 2004/07/02 20:28:06
> +++ //depot/user/jhb/preemption/i386/i386/intr_machdep.c 2004/07/16 20:14:26
> @@ -204,6 +204,8 @@
> }
> isrc->is_pic->pic_eoi_source(isrc);
> error = 0;
> + /* XXX */
> + td->td_pflags &= ~TDP_OWEPREEMPT;
> critical_exit();
> } else {
> /*
>
> --
> John Baldwin <jhb@FreeBSD.org> <>< http://www.FreeBSD.org/~jhb/
> "Power Users Use the Power to Serve" = http://www.FreeBSD.org
>
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.NEB.3.96L.1040719115338.38770K-100000>