linux-kernel - Re: [PATCH 3/3] sched: Disable affine wakeups by default

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, 25 Oct 2009 09:01:25 +0100
From:	Peter Zijlstra <peterz@...radead.org>
To:	Arjan van de Ven <arjan@...radead.org>
Cc:	mingo@...e.hu, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 3/3] sched: Disable affine wakeups by default

On Sat, 2009-10-24 at 13:07 -0700, Arjan van de Ven wrote:
> Subject: sched: Disable affine wakeups by default
> From: Arjan van de Ven <arjan@...ux.intel.com>
> 
> The global affine wakeup scheduler feature sounds nice, but there is a problem
> with this: This is ALSO a per scheduler domain feature already.
> By having the global scheduler feature enabled by default, the scheduler domains
> no longer have the option to opt out.
> 
> There are domains (for example the HT/SMT domain) that have good reason to want
> to opt out of this feature.
> 
> With this patch they can opt out, while all other domains currently default to
> the affine setting anyway.
> 
> Signed-off-by: Arjan van de Ven <arjan@...ux.intel.com>
> 

Hell no, that'll destroy many workloads. What you could possibly do is
disable it for sched domains that are known to share cache, maybe.

--
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/