Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755460AbZJAJCi (ORCPT ); Thu, 1 Oct 2009 05:02:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755334AbZJAJCh (ORCPT ); Thu, 1 Oct 2009 05:02:37 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:52157 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754910AbZJAJCh (ORCPT ); Thu, 1 Oct 2009 05:02:37 -0400 Date: Thu, 1 Oct 2009 11:01:37 +0200 From: Ingo Molnar To: Jens Axboe Cc: Tejun Heo , Peter Zijlstra , Linus Torvalds , Avi Kivity , =?iso-8859-1?Q?Fr=E9d=E9ric?= Weisbecker , jeff@garzik.org, linux-kernel@vger.kernel.org, akpm@linux-foundation.org, rusty@rustcorp.com.au, cl@linux-foundation.org, dhowells@redhat.com, arjan@linux.intel.com Subject: Re: [RFC PATCHSET] workqueue: implement concurrency managed workqueue Message-ID: <20091001090137.GE15345@elte.hu> References: <1254384558-1018-1-git-send-email-tj@kernel.org> <20091001084040.GA15345@elte.hu> <20091001084733.GO14918@kernel.dk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20091001084733.GO14918@kernel.dk> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.5 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 998 Lines: 25 * Jens Axboe wrote: > On Thu, Oct 01 2009, Ingo Molnar wrote: > > My main worry is that in practice workqueues arent all that performance > > critical - so we are shooting to optimize something that doesnt > > necessarily use all the potential goodness inherent in this approach. > > Well, the main problem with the current code is that per-cpu > workqueues are way abused. I don't look at this patchset from a > performance point of view, but rather a way to limit this huge number > of idle and pointless threads. [...] I do look at it as a potentially (and primarily) big performance feature - if only it was utilized in a place where the performance aspect mattered. Sure, the memory savings are nice too. Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/