From: Ingo Molnar <mingo@elte.hu>
To: Bill Huey <bhuey@lnxw.com>
Cc: Karim Yaghmour <karim@opersys.com>,
Kristian Benoit <kbenoit@opersys.com>,
linux-kernel@vger.kernel.org, paulmck@us.ibm.com, andrea@suse.de,
tglx@linutronix.de, pmarques@grupopie.com, bruce@andrew.cmu.edu,
nickpiggin@yahoo.com.au, ak@muc.de, sdietrich@mvista.com,
dwalker@mvista.com, hch@infradead.org, akpm@osdl.org,
rpm@xenomai.org
Subject: Re: PREEMPT_RT vs I-PIPE: the numbers, part 2
Date: Wed, 22 Jun 2005 22:05:54 +0200 [thread overview]
Message-ID: <20050622200554.GA16119@elte.hu> (raw)
In-Reply-To: <20050622192927.GA13817@nietzsche.lynx.com>
* Bill Huey <bhuey@lnxw.com> wrote:
> > target is subject to the HD test. For a pipe, this goes from 9.4us
> > to 21.6. For UDP this goes from 22us to 1070us !!! Even on a
> > system without any load, the numbers are similar. Ouch.
>
> I'm involved in other things now, but I wouldn't be surprised if it
> was some kind of scheduler bug + softirq wacked interaction. [...]
the UDP-over-localhost latency was a softirq processing bug that is
fixed in current PREEMPT_RT patches. (real over-the-network latency was
never impacted, that's why it wasnt noticed before.)
Ingo
next prev parent reply other threads:[~2005-06-22 20:13 UTC|newest]
Thread overview: 61+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-06-20 17:13 PREEMPT_RT vs I-PIPE: the numbers, part 2 Kristian Benoit
2005-06-20 18:31 ` Bill Huey
2005-06-22 16:00 ` Karim Yaghmour
2005-06-22 19:29 ` Bill Huey
2005-06-22 20:05 ` Ingo Molnar [this message]
2005-06-22 20:39 ` Karim Yaghmour
2005-06-22 22:04 ` Ingo Molnar
2005-06-22 23:03 ` Lee Revell
2005-06-22 23:52 ` Karim Yaghmour
2005-06-22 23:38 ` Karim Yaghmour
2005-06-22 23:57 ` Andrea Arcangeli
2005-06-23 0:05 ` Daniel Walker
2005-06-23 0:48 ` Karim Yaghmour
2005-06-23 0:06 ` Ingo Molnar
2005-06-23 0:47 ` Karim Yaghmour
2005-06-23 0:55 ` Bill Huey
2005-06-23 1:09 ` Karim Yaghmour
2005-06-23 1:15 ` Bill Huey
2005-06-23 1:47 ` Karim Yaghmour
2005-06-23 0:59 ` David Lang
2005-06-23 1:22 ` Karim Yaghmour
2005-06-23 1:42 ` David Lang
2005-06-23 2:09 ` Karim Yaghmour
2005-06-23 2:15 ` David Lang
2005-06-23 1:34 ` Ingo Molnar
2005-06-23 2:02 ` Karim Yaghmour
2005-06-23 3:57 ` Lee Revell
2005-06-23 4:13 ` Karim Yaghmour
2005-06-22 20:10 ` Karim Yaghmour
2005-06-22 20:15 ` Bill Huey
2005-06-21 1:55 ` Paul E. McKenney
2005-06-21 2:29 ` Karim Yaghmour
2005-06-22 1:19 ` Paul E. McKenney
2005-06-22 15:31 ` Karim Yaghmour
2005-06-22 15:27 ` Kristian Benoit
2005-06-22 16:27 ` Paul E. McKenney
2005-06-22 17:20 ` Kristian Benoit
2005-06-22 17:34 ` Ingo Molnar
2005-06-22 17:40 ` Ingo Molnar
2005-06-22 18:12 ` Karim Yaghmour
2005-06-22 18:14 ` Ingo Molnar
2005-06-22 19:04 ` Karim Yaghmour
2005-06-22 18:50 ` Paul E. McKenney
2005-06-22 19:04 ` Ingo Molnar
2005-06-22 20:17 ` Karim Yaghmour
2005-06-22 20:22 ` Ingo Molnar
2005-06-22 21:03 ` Karim Yaghmour
2005-06-22 21:10 ` Ingo Molnar
2005-06-22 21:32 ` Karim Yaghmour
2005-06-22 22:41 ` Ingo Molnar
2005-06-22 23:02 ` Karim Yaghmour
2005-06-22 21:20 ` Paul E. McKenney
2005-06-22 19:08 ` Karim Yaghmour
2005-06-23 14:48 ` Paulo Marques
2005-06-22 17:58 ` Karim Yaghmour
2005-06-22 18:47 ` Paul E. McKenney
2005-06-22 19:16 ` Karim Yaghmour
2005-06-22 21:23 ` Paul E. McKenney
2005-06-22 17:17 ` Lee Revell
2005-06-22 17:32 ` Karim Yaghmour
2005-06-29 7:43 ` PREEMPT_RT & threading IRQ 0 Ingo Molnar
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