linux-kernel - Re: [PATCH] Re: Bad network performance over 2Gbps

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: <480CC3D8.3040700@hp.com>
Date:	Mon, 21 Apr 2008 09:42:00 -0700
From:	Rick Jones <rick.jones2@...com>
To:	7eggert@....de
CC:	Kok@...r.kernel.org, Auke <auke-jan.h.kok@...el.com>,
	Ingo Molnar <mingo@...e.hu>,
	Thomas Gleixner <tglx@...utronix.de>,
	"H. Peter Anvin" <hpa@...or.com>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>,
	Anton Titov <a.titov@...t.bg>, Chris Snook <csnook@...hat.com>,
	"H. Willstrand" <h.willstrand@...il.com>, netdev@...r.kernel.org,
	Jesse Brandeburg <jesse.brandeburg@...el.com>,
	Linus Torvalds <torvalds@...ux-foundation.org>,
	Andrew Morton <akpm@...ux-foundation.org>
Subject: Re: [PATCH] Re: Bad network performance over 2Gbps

Bodo Eggert wrote:
> Kok, Auke <auke-jan.h.kok@...el.com> wrote:
> 
> 
>>[X86] IRQBALANCE: Mark as BROKEN and disable by default
>>
>>The IRQBALANCE option causes interrupts to bounce all around on SMP systems
>>quickly burying the CPU in migration cost and cache misses. Mainly affected
>>are network interrupts and this results in one CPU pegged in softirqd
>>completely.
> 
> 
> If this is the problem, maybe it would help to only balance the IRQs each
> e.g. ten seconds? Unfortunately I have no SMP system to try it out.

Be it kernel or user space, for consistent benchmark results it needs to 
be able to be turned-off without turning the code.  That leaves me in 
agreement with Stephen that if it must exist, the user space one would 
be preferable.  It can be easily terminated with extreme prejudice.

rick jones
--
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/