From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with SMTP id A2D0D6B03A6 for ; Mon, 23 Aug 2010 05:07:43 -0400 (EDT) Received: by iwn33 with SMTP id 33so4195119iwn.14 for ; Mon, 23 Aug 2010 02:07:42 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20100823071610.GL19797@csn.ul.ie> References: <20100817111018.GQ19797@csn.ul.ie> <4385155269B445AEAF27DC8639A953D7@rainbow> <20100818154130.GC9431@localhost> <565A4EE71DAC4B1A820B2748F56ABF73@rainbow> <20100819160006.GG6805@barrios-desktop> <20100820053447.GA13406@localhost> <20100820093558.GG19797@csn.ul.ie> <20100822153121.GA29389@barrios-desktop> <20100823071610.GL19797@csn.ul.ie> Date: Mon, 23 Aug 2010 18:07:41 +0900 Message-ID: Subject: Re: compaction: trying to understand the code From: Minchan Kim Content-Type: text/plain; charset=ISO-8859-1 Sender: owner-linux-mm@kvack.org To: Mel Gorman Cc: Andrew Morton , Wu Fengguang , Iram Shahzad , "linux-mm@kvack.org" , KOSAKI Motohiro List-ID: On Mon, Aug 23, 2010 at 4:16 PM, Mel Gorman wrote: > On Mon, Aug 23, 2010 at 12:31:21AM +0900, Minchan Kim wrote: >> >> >> From 560e8898295c663f02aede07b3d55880eba16c69 Mon Sep 17 00:00:00 2001 >> From: Minchan Kim >> Date: Mon, 23 Aug 2010 00:20:44 +0900 >> Subject: [PATCH] compaction: handle active and inactive fairly in too_many_isolated >> >> Iram reported compaction's too_many_isolated loops forever. >> (http://www.spinics.net/lists/linux-mm/msg08123.html) >> >> The meminfo of situation happened was inactive anon is zero. >> That's because the system has no memory pressure until then. >> While all anon pages was in active lru, compaction could select >> active lru as well as inactive lru. That's different things >> with vmscan's isolated. So we has been two too_many_isolated. >> >> While compaction can isolated pages in both active and inactive, >> current implementation of too_many_isolated only considers inactive. >> It made Iram's problem. >> >> This patch handles active and inactie with fair. >> That's because we can't expect where from and how many compaction would >> isolated pages. >> >> This patch changes (nr_isolated > nr_inactive) with >> nr_isolated > (nr_active + nr_inactive) / 2. >> >> Cc: Mel Gorman >> Cc: Wu Fengguang >> Signed-off-by: Minchan Kim > > Seems reasonable to me. > > Acked-by: Mel Gorman Thanks. > > Want to repost this as a standalone patch? Yes. It is enough to be a standalone. I will repost the patch as removing part about reporting Iram's problem. We need to dig in Iram's problem regardless of this patch. -- Kind regards, Minchan Kim -- 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