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 158686B003D for ; Fri, 6 Feb 2009 05:06:35 -0500 (EST) Received: by gxk13 with SMTP id 13so722918gxk.14 for ; Fri, 06 Feb 2009 02:06:34 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <20090206080354.GA6516@barrios-desktop> References: <20090206031125.693559239@cmpxchg.org> <20090206031324.004715023@cmpxchg.org> <20090206080354.GA6516@barrios-desktop> Date: Fri, 6 Feb 2009 19:06:34 +0900 Message-ID: <28c262360902060206h78c15a1dsf52b481c5cc1bc74@mail.gmail.com> Subject: Re: [PATCH 3/3][RFC] swsusp: shrink file cache first From: MinChan Kim Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Johannes Weiner Cc: Andrew Morton , "Rafael J. Wysocki" , Rik van Riel , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Fri, Feb 6, 2009 at 5:03 PM, MinChan Kim wrote: > Hi, Johannes. > I have some questions. > Just out of curiosity. :) > > On Fri, Feb 06, 2009 at 04:11:28AM +0100, Johannes Weiner wrote: >> File cache pages are saved to disk either through normal writeback by >> reclaim or by including them in the suspend image written to a >> swapfile. >> >> Writing them either way should take the same amount of time but doing >> normal writeback and unmap changes the fault behaviour on resume from >> prefault to on-demand paging, smoothening out resume and giving > > What do you mean "unmap"? > Why normal writeback and unmap chnages the fault behavior on resume ? Please, Ignore poor first my question. :( I agree with your opinion. >> previously cached pages the chance to stay out of memory completely if >> they are not used anymore. >> >> Another reason for preferring file page eviction is that the locality >> principle is visible in fault patterns and swap might perform really >> bad with subsequent faulting of contiguously mapped pages. > > Why do you think that swap might perform bad with subsequent faulting > of contiguusly mapped page ? > You mean normal file system is faster than swap due to readahead and > smart block of allocation ? But, I still can't understand this issue. what mean "page eviction" ? Is it reclaim or swap out ? > > -- > Kinds Regards > MinChan Kim > > -- Kinds 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