From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx155.postini.com [74.125.245.155]) by kanga.kvack.org (Postfix) with SMTP id 83C4D6B004F for ; Thu, 12 Jan 2012 22:12:31 -0500 (EST) Received: by iafj26 with SMTP id j26so4836384iaf.14 for ; Thu, 12 Jan 2012 19:12:30 -0800 (PST) Date: Fri, 13 Jan 2012 12:12:21 +0900 From: Minchan Kim Subject: Re: [PATCH v2] mm/compaction : do optimazition when the migration scanner gets no page Message-ID: <20120113031221.GA6473@barrios-desktop> References: <1326347222-9980-1-git-send-email-b32955@freescale.com> <20120112080311.GA30634@barrios-desktop.redhat.com> <20120112114835.GI4118@suse.de> <20120113005026.GA2614@barrios-desktop.redhat.com> <4F0F987E.1080001@freescale.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4F0F987E.1080001@freescale.com> Sender: owner-linux-mm@kvack.org List-ID: To: Huang Shijie Cc: Mel Gorman , akpm@linux-foundation.org, linux-mm@kvack.org On Fri, Jan 13, 2012 at 10:35:42AM +0800, Huang Shijie wrote: > Hi, > >I think simple patch is returning "return cc->nr_migratepages ? ISOLATE_SUCCESS : ISOLATE_NONE;" > >It's very clear and readable, I think. > >In this patch, what's the problem you think? > > > sorry for the wrong thread, please read the following thread: > http://marc.info/?l=linux-mm&m=132532266130861&w=2 Huang, Thanks for notice that thread. I read and if I understand correctly, the point is that Mel want to see tracepoint "trace_mm_compaction_migratepages" and account "count_vm_event(COMPACTBLOCKS);" My patch does accounting COMPACTBLOCKS so it's not a problem. The problem is my patch doesn't emit trace of "trace_mm_compaction_migratepages". But doesn't it matter? When we doesn't isolate any page at all, both argument in trace_mm_compaction_migratepages are always zero. Is it meaningful tracepoint? Do we really want it? > > Best Regards > Huang Shijie > -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org