From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933192Ab0J1IBS (ORCPT ); Thu, 28 Oct 2010 04:01:18 -0400 Received: from fgwmail7.fujitsu.co.jp ([192.51.44.37]:35019 "EHLO fgwmail7.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933065Ab0J1IBP (ORCPT ); Thu, 28 Oct 2010 04:01:15 -0400 X-SecurityPolicyCheck-FJ: OK by FujitsuOutboundMailChecker v1.3.1 From: KOSAKI Motohiro To: Andrea Arcangeli Subject: Re: [PATCH 4/7] vmscan: narrowing synchrounous lumply reclaim condition Cc: kosaki.motohiro@jp.fujitsu.com, Mel Gorman , LKML , linux-mm , Andrew Morton , Johannes Weiner , Wu Fengguang , Minchan Kim , Rik van Riel In-Reply-To: <20101027180333.GE29304@random.random> References: <20101027171643.GA4896@csn.ul.ie> <20101027180333.GE29304@random.random> Message-Id: <20101028162522.B0B5.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: Thu, 28 Oct 2010 17:00:57 +0900 (JST) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi > My tree uses compaction in a fine way inside kswapd too and tons of > systems are running without lumpy and floods of order 9 allocations > with only compaction (in direct reclaim and kswapd) without the > slighest problem. Furthermore I extended compaction for all > allocations not just that PAGE_ALLOC_COSTLY_ORDER (maybe I already > removed all PAGE_ALLOC_COSTLY_ORDER checks?). There's no good reason > not to use compaction for every allocation including 1,2,3, and things > works fine this way. Interesting. I parsed this you have compaction improvement. If so, can you please post them? Generically, 1) improve the feature 2) remove unused one is safety order. In the other hand, reverse order seems to has regression risk.