From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753150Ab0LAKRN (ORCPT ); Wed, 1 Dec 2010 05:17:13 -0500 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:48704 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750965Ab0LAKRM (ORCPT ); Wed, 1 Dec 2010 05:17:12 -0500 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Christoph Lameter Subject: Re: Free memory never fully used, swapping Cc: kosaki.motohiro@jp.fujitsu.com, Simon Kirby , Mel Gorman , Andrew Morton , linux-kernel , linux-mm@kvack.org In-Reply-To: References: <20101130092534.82D5.A69D9226@jp.fujitsu.com> Message-Id: <20101201114226.ABAB.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Mailer: Becky! ver. 2.50.07 [ja] Date: Wed, 1 Dec 2010 19:17:07 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > On Tue, 30 Nov 2010, KOSAKI Motohiro wrote: > > > This? > > Specifying a parameter to temporarily override to see if this has the > effect is ok. But this has worked for years now. There must be something > else going with with reclaim that causes these issues now. I don't think this has worked. Simon have found the corner case recently, but it is not new. So I hope you realize that high order allocation is no free lunch. __GFP_NORETRY makes no sense really. Even though we have compaction, high order reclaim is still costly operation. I don't think SLUB's high order allocation trying is bad idea. but now It does more costly trying. that's bad. Also I'm worry about SLUB assume too higher end machine. Now Both SLES and RHEL decided to don't use SLUB, instead use SLAB. Now linux community is fragmented. If you are still interesting SL*B unification, can you please consider to join corner case smashing activity?