From: Jon Masters <jcm@redhat.com>
To: Mike Kravetz <kravetz@us.ibm.com>
Cc: linux-rt-users@vger.kernel.org,
LKML <linux-kernel@vger.kernel.org>,
williams <williams@redhat.com>,
"Luis Claudio R. Goncalves" <lgoncalv@redhat.com>
Subject: Re: [RT] [RFC] simple SMI detector
Date: Mon, 26 Jan 2009 12:51:12 -0500 [thread overview]
Message-ID: <1232992272.19862.3.camel@londonpacket.bos.redhat.com> (raw)
In-Reply-To: <20090125225205.GA3783@monkey.beaverton.ibm.com>
On Sun, 2009-01-25 at 14:52 -0800, Mike Kravetz wrote:
> Any reason why you could not do SMI detection in user level code running
> at the highest RT priority?
Yeah. I had some suggestions about that already...the problem with that
is that you can't know whether measured latencies are due to SMIs /or/
other kernel latencies - maybe there's a bug or other problem? I really
want to be able to say to vendors "nope, it's definitely your problem".
So I think what'll end up happening is a user process for ease of
deployment but something like smi_detector for advanced diagnostics. And
then I just hope others will write tools like the one IBM already has
that will turn off extraneous SMI generation :)
Jon.
next prev parent reply other threads:[~2009-01-26 17:51 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-01-23 22:55 [RT] [RFC] simple SMI detector Jon Masters
2009-01-24 2:33 ` Lee Revell
2009-01-24 16:30 ` Thomas Gleixner
2009-01-25 0:57 ` Jon Masters
2009-01-25 2:12 ` Sven-Thorsten Dietrich
2009-01-25 4:02 ` Theodore Tso
2009-01-25 9:40 ` Thomas Gleixner
2009-01-25 11:49 ` Bastien ROUCARIES
2009-01-25 15:04 ` Clark Williams
2009-01-25 21:41 ` Jon Masters
2009-01-25 21:38 ` Jon Masters
2009-01-25 9:34 ` Thomas Gleixner
2009-01-25 14:07 ` Henrique de Moraes Holschuh
2009-01-25 22:52 ` Mike Kravetz
2009-01-26 17:51 ` Jon Masters [this message]
2009-01-27 2:23 ` Lee Revell
2009-01-27 2:48 ` Keith Mannthey
2009-01-27 11:22 ` Pavel Machek
2009-01-27 15:17 ` Jon Masters
2009-01-27 18:00 ` Len Brown
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