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 9BB975F0001 for ; Thu, 16 Apr 2009 02:30:38 -0400 (EDT) Date: Thu, 16 Apr 2009 14:30:24 +0800 From: Wu Fengguang Subject: Re: [RFC][PATCH] proc: export more page flags in /proc/kpageflags Message-ID: <20090416063024.GA5803@localhost> References: <20090414071159.GV14687@one.firstfloor.org> <20090415131800.GA11191@localhost> <20090416111108.AC55.A69D9226@jp.fujitsu.com> <20090416034918.GB20162@localhost> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090416034918.GB20162@localhost> Sender: owner-linux-mm@kvack.org To: KOSAKI Motohiro Cc: Andi Kleen , Andrew Morton , LKML , "linux-mm@kvack.org" List-ID: On Thu, Apr 16, 2009 at 11:49:18AM +0800, Wu Fengguang wrote: > On Thu, Apr 16, 2009 at 10:26:51AM +0800, KOSAKI Motohiro wrote: > > tatus: RO > > Content-Length: 13245 > > Lines: 380 > > > > Hi > > > > > > > > On Tue, Apr 14, 2009 at 12:37:10PM +0800, KOSAKI Motohiro wrote: > > > > > > > > Export the following page flags in /proc/kpageflags, > > > > > > > > just in case they will be useful to someone: > > > > > > > > > > > > > > > > - PG_swapcache > > > > > > > > - PG_swapbacked > > > > > > > > - PG_mappedtodisk > > > > > > > > - PG_reserved > > > > > > > > PG_reserved should be exported as PG_KERNEL or somesuch. > > > > > > PG_KERNEL could be misleading. PG_reserved obviously do not cover all > > > (or most) kernel pages. So I'd prefer to export PG_reserved as it is. > > > > > > It seems that the vast amount of free pages are marked PG_reserved: > > > > Can I review the document at first? > > if no good document for administrator, I can't ack exposing PG_reserved. > > btw, is this the expected behavior to mark so many free pages as PG_reserved? > Last time I looked at it, in 2.6.27, the free pages simply don't have > any flags set. > > //Or maybe it's a false reporting of my tool. Will double check. Ah it's my fault. Something goes wrong when I convert the page-types data structure from a huge array to hash table. Here is the correct output: # echo 1 > /proc/sys/vm/drop_caches # ./page-types flags page-count MB symbolic-flags long-symbolic-flags 0x000000000000 479149 1871 ___________________________ 0x000000004000 19258 75 ______________r____________ reserved 0x000000008000 16 0 _______________o___________ compound 0x004000008000 3655 14 _______________o__________T compound,compound_tail 0x000000008014 1 0 __R_D__________o___________ referenced,dirty,compound 0x004000008014 4 0 __R_D__________o__________T referenced,dirty,compound,compound_tail 0x000000000020 1 0 _____l_____________________ lru 0x000000000028 58 0 ___U_l_____________________ uptodate,lru 0x00000000203c 17 0 __RUDl_______b_____________ referenced,uptodate,dirty,lru,swapbacked 0x000200000064 20 0 __R__lA______________P_____ referenced,lru,active,private 0x000200000068 5 0 ___U_lA______________P_____ uptodate,lru,active,private 0x00000000006c 17 0 __RU_lA____________________ referenced,uptodate,lru,active 0x00020000006c 2 0 __RU_lA______________P_____ referenced,uptodate,lru,active,private 0x000000002078 1 0 ___UDlA______b_____________ uptodate,dirty,lru,active,swapbacked 0x000000000228 1 0 ___U_l___x_________________ uptodate,lru,reclaim 0x000000000400 3600 14 __________B________________ buddy 0x000000000804 1 0 __R________m_______________ referenced,mmap 0x000000002808 6 0 ___U_______m_b_____________ uptodate,mmap,swapbacked 0x000000002828 974 3 ___U_l_____m_b_____________ uptodate,lru,mmap,swapbacked 0x00000000082c 1 0 __RU_l_____m_______________ referenced,uptodate,lru,mmap 0x000000000868 1501 5 ___U_lA____m_______________ uptodate,lru,active,mmap 0x000000002868 2696 10 ___U_lA____m_b_____________ uptodate,lru,active,mmap,swapbacked 0x00000000086c 969 3 __RU_lA____m_______________ referenced,uptodate,lru,active,mmap 0x00000000286c 17 0 __RU_lA____m_b_____________ referenced,uptodate,lru,active,mmap,swapbacked 0x000000002878 2 0 ___UDlA____m_b_____________ uptodate,dirty,lru,active,mmap,swapbacked 0x000000008880 694 2 _______S___m___o___________ slab,mmap,compound 0x000000000880 1183 4 _______S___m_______________ slab,mmap 0x0000000088c0 62 0 ______AS___m___o___________ active,slab,mmap,compound 0x0000000008c0 57 0 ______AS___m_______________ active,slab,mmap total 513968 2007 Thanks, Fengguang -- 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