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:	Wed, 26 Sep 2007 10:12:40 +0800
From:	"John Ye" <johny@...mco.com.cn>
To:	<hadi@...erus.ca>,
	"Stephen Hemminger" <shemminger@...ux-foundation.org>
Cc:	"David Miller" <davem@...emloft.net>, <netdev@...r.kernel.org>,
	<kuznet@....inr.ac.ru>, <pekkas@...core.fi>, <jmorris@...ei.org>,
	<kaber@...eworks.de>, <iceburgue@...il.com>
Subject: Re: [PATCH: 2.6.13-15-SMP 3/3] network: concurrentlyrunsoftirqnetwork code on SMP

Jamal & Stephen,

I found BSS-hash paper you mentioned and have browsed it briefly.
The issue "may end sending all your packets to one cpu" might be dealt with
by
cpu hash (srcip + dstip) % nr_cpus, plus checking cpu balance periodically,
shift cpu by an extra seed value?

Any way, the cpu hash code must not be too expensive because every incoming
packet hits the path.

We are going to do further study on this BSS thing.

__do_IRQ has a tendency to collect same IRQ on different CPUs into one CPU
when NIC is busy(by IRQ_PENDING & IRQ_INPROGRESS control skill). so,
dispatch the load to SMP here may be good thing(?).

Thanks.

John Ye


----- Original Message -----
From: "jamal" <hadi@...erus.ca>
To: "Stephen Hemminger" <shemminger@...ux-foundation.org>
Cc: "john ye" <johny@...mco.com.cn>; "David Miller" <davem@...emloft.net>;
<netdev@...r.kernel.org>; <kuznet@....inr.ac.ru>; <pekkas@...core.fi>;
<jmorris@...ei.org>; <kaber@...eworks.de>; <iceburgue@...il.com>
Sent: Wednesday, September 26, 2007 6:22 AM
Subject: Re: [PATCH: 2.6.13-15-SMP 3/3] network:
concurrentlyrunsoftirqnetwork code on SMP


> On Tue, 2007-25-09 at 09:03 -0700, Stephen Hemminger wrote:
>
> > There is a standard hash called RSS, that many drivers support because
it is
> > used by other operating systems.
>
> I think any stateless/simple thing will do (something along the lines
> what 802.1ad does for trunk, a 5 classical five tuple etc).
>
> Having solved the reordering problem in such a stateless way introduces
> a loadbalancing setback; you may end sending all your packets to one cpu
> (a problem Mr Ye didnt have when he was re-orderding ;->).
>
> cheers,
> jamal
>
>


-
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Powered by blists - more mailing lists