From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764784AbXGJSqR (ORCPT ); Tue, 10 Jul 2007 14:46:17 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754737AbXGJSqF (ORCPT ); Tue, 10 Jul 2007 14:46:05 -0400 Received: from netops-testserver-4-out.sgi.com ([192.48.171.29]:37165 "EHLO relay.sgi.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754647AbXGJSqD (ORCPT ); Tue, 10 Jul 2007 14:46:03 -0400 Date: Tue, 10 Jul 2007 11:46:00 -0700 (PDT) From: Christoph Lameter X-X-Sender: clameter@schroedinger.engr.sgi.com To: Nick Piggin cc: Mel Gorman , Andrew Morton , kenchen@google.com, jschopp@austin.ibm.com, apw@shadowen.org, kamezawa.hiroyu@jp.fujitsu.com, a.p.zijlstra@chello.nl, y-goto@jp.fujitsu.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: -mm merge plans -- anti-fragmentation In-Reply-To: <20070710130356.GG8779@wotan.suse.de> Message-ID: References: <20070710102043.GA20303@skynet.ie> <20070710130356.GG8779@wotan.suse.de> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 10 Jul 2007, Nick Piggin wrote: > I realise in your pragmatic approach, you are encouraging users to > put fallbacks in place in case a higher order page cannot be allocated, > but I don't think either higher order pagecache or higher order slubs > have such fallbacks (fsblock or a combination of fsblock and higher > order pagecache could have, but...). We have run mm kernels for month now without the need of a fallback. I purpose of ZONE_MOVABLE was to guarantee that higher order pages could be reclaimed and thus make the scheme reliable? The experience so far shows that the approach works reliably. If there are issues then they need to be fixed. Putting in workarounds in other places such as in fsblock may just be hiding problems if there are any.