Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752745AbWKGU7P (ORCPT ); Tue, 7 Nov 2006 15:59:15 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752629AbWKGU7P (ORCPT ); Tue, 7 Nov 2006 15:59:15 -0500 Received: from omx2-ext.sgi.com ([192.48.171.19]:16870 "EHLO omx2.sgi.com") by vger.kernel.org with ESMTP id S1752626AbWKGU7O (ORCPT ); Tue, 7 Nov 2006 15:59:14 -0500 Date: Tue, 7 Nov 2006 12:59:05 -0800 (PST) From: Christoph Lameter To: Ingo Molnar cc: "Siddha, Suresh B" , akpm@osdl.org, mm-commits@vger.kernel.org, nickpiggin@yahoo.com.au, linux-kernel@vger.kernel.org Subject: Re: + sched-use-tasklet-to-call-balancing.patch added to -mm tree In-Reply-To: <20061107203147.GB4753@elte.hu> Message-ID: References: <200611032205.kA3M5wmJ003178@shell0.pdx.osdl.net> <20061107073248.GB5148@elte.hu> <20061107093112.A3262@unix-os.sc.intel.com> <20061107095049.B3262@unix-os.sc.intel.com> <20061107203147.GB4753@elte.hu> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 829 Lines: 19 On Tue, 7 Nov 2006, Ingo Molnar wrote: > Per-CPU tasklets are equivalent to softirqs, with extra complexity and > overhead ontop of it :-) > > so please just introduce a rebalance softirq and attach the scheduling > rebalance tick to it. But i'd suggest to re-test on the 4096-CPU box, > maybe what 'fixed' your workload was the global serialization of the > tasklet. With a per-CPU softirq approach we are i think back to the same > situation that broke your system before. What broke the system was the disabling of interrupts over long time periods during load balancing. - 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/