From: Ingo Molnar <mingo@elte.hu>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: Robert Swan <swan.r.l@gmail.com>,
Linus Torvalds <torvalds@linux-foundation.org>,
linux-kernel@vger.kernel.org,
Arjan van de Ven <arjan@infradead.org>
Subject: Re: [bisected] pty performance problem
Date: Sun, 22 Nov 2009 13:42:09 +0100 [thread overview]
Message-ID: <20091122124209.GA30965@elte.hu> (raw)
In-Reply-To: <20091122122312.71a343d9@lxorguk.ukuu.org.uk>
* Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:
> On Sun, 22 Nov 2009 07:39:26 +0100
> Ingo Molnar <mingo@elte.hu> wrote:
>
> >
> > (Cc:-ed Alan and Linus - mail repeated below. eot.)
>
> I saw it and replied already. The kernel now queues the work for the
> pty as it does normal tty devices. If the CPU load is that low and
> nothing else is happening it makes me wonder what the scheduler thinks
> it is doing ?
Would be nice to see the testcase, but by the looks if it there appears
to be a jiffy delay somewhere - not a scheduler delay. On an idle box
the scheduler will run any runnable tasks, with no delay.
Ingo
next prev parent reply other threads:[~2009-11-22 12:42 UTC|newest]
Thread overview: 20+ messages / expand[flat|nested] mbox.gz Atom feed top
2009-11-21 22:23 [bisected] pty performance problem Robert Swan
2009-11-21 23:23 ` Alan Cox
2009-11-22 0:27 ` Robert Swan
2009-11-22 12:29 ` Alan Cox
2009-11-22 12:41 ` Mike Galbraith
2009-11-22 21:37 ` Robert Swan
2009-11-22 6:39 ` Ingo Molnar
2009-11-22 7:15 ` Arjan van de Ven
2009-11-22 21:56 ` Robert Swan
2009-11-22 12:23 ` Alan Cox
2009-11-22 12:42 ` Ingo Molnar [this message]
2009-11-23 5:00 ` Mike Galbraith
2009-11-23 10:28 ` Alan Cox
2009-11-23 11:31 ` Alan Cox
2009-11-23 11:48 ` Ingo Molnar
2009-11-23 11:59 ` Alan Cox
2009-11-23 12:04 ` Ingo Molnar
2009-11-23 13:34 ` Alan Cox
2009-11-23 17:48 ` Ingo Molnar
2011-07-09 6:29 ` Robert Swan
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