From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752201AbYITQCZ (ORCPT ); Sat, 20 Sep 2008 12:02:25 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750786AbYITQCP (ORCPT ); Sat, 20 Sep 2008 12:02:15 -0400 Received: from gateway-1237.mvista.com ([63.81.120.158]:15169 "EHLO gateway-1237.mvista.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750780AbYITQCP (ORCPT ); Sat, 20 Sep 2008 12:02:15 -0400 Subject: Re: [PATCH 0/2]: Remote softirq invocation infrastructure. From: Daniel Walker To: Arjan van de Ven Cc: David Miller , linux-kernel@vger.kernel.org, netdev@vger.kernel.org, jens.axboe@oracle.com, steffen.klassert@secunet.com In-Reply-To: <20080920084512.58f7fb08@infradead.org> References: <20080919.234824.223177211.davem@davemloft.net> <1221924561.1343.121.camel@localhost.localdomain> <20080920084512.58f7fb08@infradead.org> Content-Type: text/plain Date: Sat, 20 Sep 2008 09:02:09 -0700 Message-Id: <1221926529.1343.140.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.22.3.1 (2.22.3.1-1.fc9) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, 2008-09-20 at 08:45 -0700, Arjan van de Ven wrote: > On Sat, 20 Sep 2008 08:29:21 -0700 > > > > > Jen's, as stated, has block layer uses for this. I intend to use > > > this for receive side flow seperation on non-multiqueue network > > > cards. And Steffen Klassert has a set of IPSEC parallelization > > > changes that can very likely make use of this. > > > > What's the benefit that you (or Jens) sees from migrating softirqs > > from specific cpu's to others? > > it means you do all the processing on the CPU that submitted the IO in > the first place, and likely still has the various metadata pieces in > its CPU cache (or at least you know you won't need to bounce them over) In the case of networking and block I would think a lot of the softirq activity is asserted from userspace.. Maybe the scheduler shouldn't be migrating these tasks, or could take this softirq activity into account .. Daniel