linux-kernel - Re: [bisected] pty performance problem

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20091122124209.GA30965@elte.hu>
Date:	Sun, 22 Nov 2009 13:42:09 +0100
From:	Ingo Molnar <mingo@...e.hu>
To:	Alan Cox <alan@...rguk.ukuu.org.uk>
Cc:	Robert Swan <swan.r.l@...il.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	linux-kernel@...r.kernel.org,
	Arjan van de Ven <arjan@...radead.org>
Subject: Re: [bisected] pty performance problem


* Alan Cox <alan@...rguk.ukuu.org.uk> wrote:

> On Sun, 22 Nov 2009 07:39:26 +0100
> Ingo Molnar <mingo@...e.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
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/