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From: Ingo Molnar <mingo@elte.hu>
To: Karim Yaghmour <karim@opersys.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [RFC][PATCH] Restricted hard realtime
Date: Thu, 28 Oct 2004 15:16:22 +0200	[thread overview]
Message-ID: <20041028131622.GA13744@elte.hu> (raw)
In-Reply-To: <4180DF18.5060808@opersys.com>


* Karim Yaghmour <karim@opersys.com> wrote:

> >with -RT-V0.3 i get lower than 20 usec _maximum_ latencies during
> >'./hackbench 20'. (the average latency is 1 usec) So while i'm not yet
> >in the sub-femtosecond category, things are looking pretty good in
> >PREEMPT_REALTIME land :)
> 
> Just curious: what's the setup here? (CPU speed, peripherals, distro,
> applications being run to load the system, etc.) [...]

2 GHz Athlon running stock Fedora Core. './hackbench 20' was the
workload.

> I'm assuming that the timings are measured using the tracing
> functionality currently in the patches.

no, i used a user-space timing app called 'realfeel', but the numbers
were corroborated by the in-kernel tracer too.

but ... the best test would be if you tried the patch, it's not hard ;)
There are newer versions since i did the above measurement and testing
feedback is always welcome.

	Ingo

  reply	other threads:[~2004-10-28 13:16 UTC|newest]

Thread overview: 21+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-10-23 19:47 [RFC][PATCH] Restricted hard realtime Paul E. McKenney
2004-10-23 20:17 ` Ingo Molnar
2004-10-23 20:29   ` Paul E. McKenney
2004-10-24 18:18   ` Paul E. McKenney
2004-10-25 12:26     ` Dimitri Sivanich
2004-10-23 20:22 ` Thomas Gleixner
2004-10-23 21:24   ` Paul E. McKenney
2004-10-23 22:06     ` Jon Masters
2004-10-24 15:32       ` Paul E. McKenney
2004-10-24 21:08         ` Jon Masters
2004-10-24 21:23           ` Ingo Molnar
2004-10-24 21:49             ` Jon Masters
2004-10-24 21:52           ` Paul E. McKenney
2004-10-27  3:16 ` Karim Yaghmour
2004-10-27  4:29   ` Andrew Morton
2004-10-27  8:10     ` Ingo Molnar
2004-10-28 11:59       ` Karim Yaghmour
2004-10-28 13:16         ` Ingo Molnar [this message]
2004-10-28 11:54     ` Karim Yaghmour
2004-10-28 13:04       ` john cooper
2004-10-27 22:35   ` Bill Huey

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