Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1765463AbXHFWrt (ORCPT ); Mon, 6 Aug 2007 18:47:49 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1761850AbXHFWrk (ORCPT ); Mon, 6 Aug 2007 18:47:40 -0400 Received: from dsl081-085-152.lax1.dsl.speakeasy.net ([64.81.85.152]:38316 "EHLO moonbase.phunq.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1761101AbXHFWrj (ORCPT ); Mon, 6 Aug 2007 18:47:39 -0400 From: Daniel Phillips To: Christoph Lameter Subject: Re: [PATCH 02/10] mm: system wide ALLOC_NO_WATERMARK Date: Mon, 6 Aug 2007 15:47:30 -0700 User-Agent: KMail/1.9.5 Cc: Matt Mackall , Peter Zijlstra , linux-kernel@vger.kernel.org, linux-mm@kvack.org, David Miller , Andrew Morton , Daniel Phillips , Pekka Enberg , Lee Schermerhorn , Steve Dickson References: <20070806102922.907530000@chello.nl> <20070806201257.GG11115@waste.org> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200708061547.30681.phillips@phunq.net> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1202 Lines: 30 (What Peter already wrote, but in different words) On Monday 06 August 2007 13:19, Christoph Lameter wrote: > The solution may be as simple as configuring the reserves right and > avoid the unbounded memory allocations. Exactly. That is what this patch set is about. This is the part that provides some hooks to extend the traditional reserves to be able to handle some of the more difficult situations. > That is possible if one > would make sure that the network layer triggers reclaim once in a > while. No. It does no good at all for network to do a bunch of work reclaiming, then have some other random task (for example, a heavy writer) swoop in and grab the reclaimed memory before net can use it. Also, net allocates memory in interrupt context where shrink_caches is not possible. The correct solution is to _reserve_ the memory net needs for vm writeout, which is in Peter's next patch set coming down the pipe. Regards, Daniel - 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/