From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 779596B02A3 for ; Thu, 8 Jul 2010 20:46:40 -0400 (EDT) Received: from m4.gw.fujitsu.co.jp ([10.0.50.74]) by fgwmail5.fujitsu.co.jp (Fujitsu Gateway) with ESMTP id o690kasC017918 for (envelope-from kosaki.motohiro@jp.fujitsu.com); Fri, 9 Jul 2010 09:46:36 +0900 Received: from smail (m4 [127.0.0.1]) by outgoing.m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 728F345DE4D for ; Fri, 9 Jul 2010 09:46:36 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (s4.gw.fujitsu.co.jp [10.0.50.94]) by m4.gw.fujitsu.co.jp (Postfix) with ESMTP id 5076245DE6E for ; Fri, 9 Jul 2010 09:46:36 +0900 (JST) Received: from s4.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id 30B991DB8040 for ; Fri, 9 Jul 2010 09:46:36 +0900 (JST) Received: from ml14.s.css.fujitsu.com (ml14.s.css.fujitsu.com [10.249.87.104]) by s4.gw.fujitsu.co.jp (Postfix) with ESMTP id D5A641DB803E for ; Fri, 9 Jul 2010 09:46:32 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH v2 2/2] vmscan: shrink_slab() require number of lru_pages, not page order In-Reply-To: References: <20100708133152.5e556508.akpm@linux-foundation.org> Message-Id: <20100709092124.CD5A.A69D9226@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Date: Fri, 9 Jul 2010 09:46:32 +0900 (JST) Sender: owner-linux-mm@kvack.org To: Christoph Lameter Cc: kosaki.motohiro@jp.fujitsu.com, Andrew Morton , LKML , linux-mm , Mel Gorman , Rik van Riel , Minchan Kim , Johannes Weiner List-ID: > On Thu, 8 Jul 2010, Andrew Morton wrote: > > > > AFAICT this is not argument error but someone changed the naming of the > > > parameter. > > > > It's been there since day zero: > > > > : commit 2a16e3f4b0c408b9e50297d2ec27e295d490267a > > : Author: Christoph Lameter > > : AuthorDate: Wed Feb 1 03:05:35 2006 -0800 > > : Commit: Linus Torvalds > > : CommitDate: Wed Feb 1 08:53:16 2006 -0800 > > : > > : [PATCH] Reclaim slab during zone reclaim > > That only shows that the order parameter was passed to shrink_slab() which > is what I remember being done intentionally. > > Vaguely recall that this was necessary to avoid shrink_slab() throwing out > too many pages for higher order allocs. But It make opposite effect. number of scanning objects of shrink_slab() are lru_scanned max_pass basic_scan_objects = 4 x ------------- x ----------------------------- lru_pages shrinker->seeks (default:2) scan_objects = min(basic_scan_objects, max_pass * 2) That said, small lru_pages parameter makes too many slab dropping. Practically, zone-reclaim always take max_pass*2. about inode, shrink_icache_memory() takes number of unused inode as max_pass. It mean one shrink_slab() calling drop all icache. Is this optimal behavior? why? Am I missing something? > Initially zone_reclaim was full of heuristics that later were replaced by > counter as the new ZVCs became available and gradually better ways of > accounting for pages became possible. -- 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