Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S262661AbVDHC3E (ORCPT ); Thu, 7 Apr 2005 22:29:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S262662AbVDHC3E (ORCPT ); Thu, 7 Apr 2005 22:29:04 -0400 Received: from smtp205.mail.sc5.yahoo.com ([216.136.129.95]:19370 "HELO smtp205.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S262661AbVDHC26 (ORCPT ); Thu, 7 Apr 2005 22:28:58 -0400 Subject: Re: 2.6.12-rc2-mm1 From: Nick Piggin To: "Siddha, Suresh B" Cc: Andrew Morton , lkml , Ingo Molnar In-Reply-To: <20050407180810.A10873@unix-os.sc.intel.com> References: <20050405000524.592fc125.akpm@osdl.org> <42523F5D.7020201@yahoo.com.au> <20050405115113.A17809@unix-os.sc.intel.com> <42541830.1010201@yahoo.com.au> <20050407180810.A10873@unix-os.sc.intel.com> Content-Type: text/plain Date: Fri, 08 Apr 2005 12:28:49 +1000 Message-Id: <1112927329.11550.4.camel@npiggin-nld.site> Mime-Version: 1.0 X-Mailer: Evolution 2.0.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1399 Lines: 35 On Thu, 2005-04-07 at 18:08 -0700, Siddha, Suresh B wrote: > On Thu, Apr 07, 2005 at 03:11:12AM +1000, Nick Piggin wrote: > > Using the attached patch, a puny dual PIII-650 with ~400MB RAM swapped > > itself to death after 20000 infinite loop tasks had been pinned to one > > of the CPUs. See how you go. > > Its goes well beyond the initial 7000 number I mentioned. Thanks. > OK, good thanks for testing that. I'll send it to Andrew. > One side-effect of this patch is: for example we have only two processes > running on a cpu and both are pinned to that cpu. If someone comes and > changes the affinity of one of these processes to all cpu's in the system, > then it might take MAX_PINNED_INTERVAL before this process moves to an idle cpu. > Yeah, that is true. OTOH it is a bit of a special case, and our multiprocessor scheduling in general practically shuts down when we have a situation with a single queue with a lot of pinned tasks. What did I have for MAX_PINNED_INTERVAL? ~1second. I guess that could come down a bit - maybe 1/4 or 1/2 a second? I think it is a "good enough for now" kind of situation. -- SUSE Labs, Novell Inc. - 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/