From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752689AbZKAOp0 (ORCPT ); Sun, 1 Nov 2009 09:45:26 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752390AbZKAOpY (ORCPT ); Sun, 1 Nov 2009 09:45:24 -0500 Received: from mx1.redhat.com ([209.132.183.28]:31623 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752351AbZKAOpY (ORCPT ); Sun, 1 Nov 2009 09:45:24 -0500 Message-ID: <4AED9EB4.5080601@redhat.com> Date: Sun, 01 Nov 2009 09:44:04 -0500 From: Rik van Riel Organization: Red Hat, Inc User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.4pre) Gecko/20090922 Fedora/3.0-3.9.b4.fc12 Lightning/1.0pre Thunderbird/3.0b4 MIME-Version: 1.0 To: Pavel Machek CC: David Rientjes , Andrew Morton , Mel Gorman , stable@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Frans Pop , Jiri Kosina , Sven Geggus , Karol Lewandowski , Tobias Oetiker , KOSAKI Motohiro , Pekka Enberg , Christoph Lameter , Stephan von Krawczynski , kernel-testers@vger.kernel.org Subject: Re: [PATCH 2/3] page allocator: Do not allow interrupts to use ALLOC_HARDER References: <1256650833-15516-1-git-send-email-mel@csn.ul.ie> <1256650833-15516-3-git-send-email-mel@csn.ul.ie> <20091027130924.fa903f5a.akpm@linux-foundation.org> <20091031184054.GB1475@ucw.cz> <20091031201158.GB29536@elf.ucw.cz> <20091031222905.GA32720@elf.ucw.cz> <4AECC04B.9060808@redhat.com> <20091101073527.GB32720@elf.ucw.cz> In-Reply-To: <20091101073527.GB32720@elf.ucw.cz> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/01/2009 02:35 AM, Pavel Machek wrote: >>> I believe it would be better to simply remove it. >> >> You are against trying to give the realtime tasks a best effort >> advantage at memory allocation? > > Yes. Those memory reserves were for kernel, GPF_ATOMIC and stuff. Now > realtime tasks are allowed to eat into them. That feels wrong. > > "realtime" tasks are not automatically "more important". > >> Realtime apps often *have* to allocate memory on the kernel side, >> because they use network system calls, etc... > > So what? As soon as they do that, they lose any guarantees, anyway. They might lose the absolute guarantee, but that's no reason not to give it our best effort! -- All rights reversed. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rik van Riel Subject: Re: [PATCH 2/3] page allocator: Do not allow interrupts to use ALLOC_HARDER Date: Sun, 01 Nov 2009 09:44:04 -0500 Message-ID: <4AED9EB4.5080601@redhat.com> References: <1256650833-15516-1-git-send-email-mel@csn.ul.ie> <1256650833-15516-3-git-send-email-mel@csn.ul.ie> <20091027130924.fa903f5a.akpm@linux-foundation.org> <20091031184054.GB1475@ucw.cz> <20091031201158.GB29536@elf.ucw.cz> <20091031222905.GA32720@elf.ucw.cz> <4AECC04B.9060808@redhat.com> <20091101073527.GB32720@elf.ucw.cz> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20091101073527.GB32720@elf.ucw.cz> Sender: owner-linux-mm@kvack.org List-Id: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: Pavel Machek Cc: David Rientjes , Andrew Morton , Mel Gorman , stable@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Frans Pop , Jiri Kosina , Sven Geggus , Karol Lewandowski , Tobias Oetiker , KOSAKI Motohiro , Pekka Enberg , Christoph Lameter , Stephan von Krawczynski , kernel-testers@vger.kernel.org On 11/01/2009 02:35 AM, Pavel Machek wrote: >>> I believe it would be better to simply remove it. >> >> You are against trying to give the realtime tasks a best effort >> advantage at memory allocation? > > Yes. Those memory reserves were for kernel, GPF_ATOMIC and stuff. Now > realtime tasks are allowed to eat into them. That feels wrong. > > "realtime" tasks are not automatically "more important". > >> Realtime apps often *have* to allocate memory on the kernel side, >> because they use network system calls, etc... > > So what? As soon as they do that, they lose any guarantees, anyway. They might lose the absolute guarantee, but that's no reason not to give it our best effort! -- All rights reversed. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org