Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754313Ab1C1N4P (ORCPT ); Mon, 28 Mar 2011 09:56:15 -0400 Received: from mail-ew0-f46.google.com ([209.85.215.46]:40961 "EHLO mail-ew0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754016Ab1C1N4O (ORCPT ); Mon, 28 Mar 2011 09:56:14 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=QSxOguKxl/pPF+PQy+0SA0bh3adYYhIl68CKpfLU68zl8o0kSxQgdPjuDRQyH2cQn7 PvU257dfbjT8ykL5p2KcSwysyMNiqMTH9zLlgN58iEfnhseyywiogIAEvh6dTtzT4q3g rooGNc0mSzQ9ETFriyHLrhu/85DxHXbpGHYy4= Date: Mon, 28 Mar 2011 10:56:01 -0300 From: "Luis Claudio R. Goncalves" To: Peter Zijlstra Cc: Minchan Kim , KOSAKI Motohiro , linux-kernel@vger.kernel.org, Andrew Morton , David Rientjes , Linus Torvalds , Rik van Riel , Oleg Nesterov , linux-mm , Andrey Vagin , Hugh Dickins , KAMEZAWA Hiroyuki Subject: Re: [PATCH 2/5] Revert "oom: give the dying task a higher priority" Message-ID: <20110328135601.GO19007@uudg.org> References: <20110315153801.3526.A69D9226@jp.fujitsu.com> <20110322194721.B05E.A69D9226@jp.fujitsu.com> <20110322200657.B064.A69D9226@jp.fujitsu.com> <20110324152757.GC1938@barrios-desktop> <1301305896.4859.8.camel@twins> <20110328122125.GA1892@barrios-desktop> <1301315307.4859.13.camel@twins> <20110328124025.GC1892@barrios-desktop> <20110328131029.GN19007@uudg.org> <1301318293.4859.19.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1301318293.4859.19.camel@twins> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1956 Lines: 49 On Mon, Mar 28, 2011 at 03:18:13PM +0200, Peter Zijlstra wrote: | On Mon, 2011-03-28 at 10:10 -0300, Luis Claudio R. Goncalves wrote: | > | There was meaningless code in there. I guess it was in there from CFS. | > | Thanks for the explanation, Peter. | > | > Yes, it was CFS related: | > | > p = find_lock_task_mm(p); | > ... | > p->rt.time_slice = HZ; <<---- THIS | | CFS has never used rt.time_slice, that's always been a pure SCHED_RR | thing. | | > Peter, would that be effective to boost the priority of the dying task? | | The thing you're currently doing, making it SCHED_FIFO ? I meant the p->rt.time_slice line, but you already answered my question. Thanks :) | > I mean, in the context of SCHED_OTHER tasks would it really help the dying | > task to be scheduled sooner to release its resources? | | That very much depends on how all this stuff works, I guess if everybody | serializes on OOM and only the first will actually kill a task and all | the waiting tasks will try to allocate a page again before also doing | the OOM thing, and the pending tasks are woken after the OOM target task | has completed dying.. then I don't see much point in boosting things, | since everybody interested in memory will block and eventually only the | dying task will be left running. | | Its been a very long while since I stared at the OOM code.. | | > If so, as we remove | > the code in commit 93b43fa5508 we should re-add that old code. | | It doesn't make any sense to fiddle with rt.time_slice afaict. ---end quoted text--- -- [ Luis Claudio R. Goncalves Red Hat - Realtime Team ] [ Fingerprint: 4FDD B8C4 3C59 34BD 8BE9 2696 7203 D980 A448 C8F8 ] -- 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/