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]
Date:	Sun, 16 Mar 2008 22:16:36 -0700
From:	"Ray Lee" <ray-lk@...rabbit.org>
To:	"Nick Piggin" <nickpiggin@...oo.com.au>
Cc:	"Peter Zijlstra" <peterz@...radead.org>,
	"Ingo Molnar" <mingo@...e.hu>,
	"LKML," <linux-kernel@...r.kernel.org>
Subject: Re: Poor PostgreSQL scaling on Linux 2.6.25-rc5 (vs 2.6.22)

On Sun, Mar 16, 2008 at 5:44 PM, Nick Piggin <nickpiggin@...oo.com.au> wrote:
>  I don't see how it is really helpful for interactive processes either.
>  By definition, if they are not CPU bound, then they should be run
>  quite soon after waking up; if they are CPU bound, then reducing
>  efficiency by increasing context switches is effectively going to
>  increase their latency anyway.

How? Are you saying that switching the granularity to, say, 25ms, will
*decrease* the latency of interactive tasks?

And the efficiency we're talking about reducing here is due to the
fact that tasks are hitting cold caches more times per second when the
granularity is smaller, correct? Or are you concerned by another
issue?

> Can this be changed by default, please?

Not without benchmarks of interactivity, please. There are far, far
more linux desktops than there are servers. People expect to have to
tune servers (I do, for the servers I maintain). People don't expect
to have to tune a desktop to make it run well.
--
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/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ