From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail190.messagelabs.com (mail190.messagelabs.com [216.82.249.51]) by kanga.kvack.org (Postfix) with ESMTP id 1DD1F6B004D for ; Mon, 9 Nov 2009 05:11:35 -0500 (EST) Date: Mon, 9 Nov 2009 10:11:28 +0000 From: Mel Gorman Subject: Re: [PATCH 2/3] page allocator: Do not allow interrupts to use ALLOC_HARDER Message-ID: <20091109101128.GB6657@csn.ul.ie> References: <20091031184054.GB1475@ucw.cz> <20091031201158.GB29536@elf.ucw.cz> <4AECCF6A.4020206@redhat.com> <20091104090140.GA14694@elf.ucw.cz> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <20091104090140.GA14694@elf.ucw.cz> Sender: owner-linux-mm@kvack.org To: Pavel Machek Cc: David Rientjes , Christoph Lameter , Rik van Riel , Andrew Morton , 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 , Stephan von Krawczynski , kernel-testers@vger.kernel.org List-ID: On Wed, Nov 04, 2009 at 10:01:40AM +0100, Pavel Machek wrote: > > > I hope we can move this to another thread if people would like to remove > > this exemption completely instead of talking about this trivial fix, which > > I doubt there's any objection to. > > I'm arguing that this "trivial fix" is wrong, and that you should just > remove those two lines. > > If going into reserves from interrupts hurts, doing that from task > context will hurt, too. "realtime" task should not be normally allowed > to "hurt" the system like that. > Pavel As David points out, it has been the behaviour of the system for 4 years and removing it should be made as a separate decision and not in the guise of a fix. In the particular case causing concern, there are a lot more allocations from interrupt due to network receive than there are from the activities of tasks with a high priority. -- Mel Gorman Part-time Phd Student Linux Technology Center University of Limerick IBM Dublin Software Lab -- 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