From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx111.postini.com [74.125.245.111]) by kanga.kvack.org (Postfix) with SMTP id C17E76B005A for ; Tue, 10 Jan 2012 04:25:48 -0500 (EST) Date: Tue, 10 Jan 2012 09:25:43 +0000 From: Mel Gorman Subject: Re: [PATCH] mm/compaction : do optimazition when the migration scanner gets no page Message-ID: <20120110092543.GA4118@suse.de> References: <1325825861-3702-1-git-send-email-b32955@freescale.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline In-Reply-To: <1325825861-3702-1-git-send-email-b32955@freescale.com> Sender: owner-linux-mm@kvack.org List-ID: To: Huang Shijie Cc: akpm@linux-foundation.org, linux-mm@kvack.org, shijie8@gmail.com On Fri, Jan 06, 2012 at 12:57:41PM +0800, Huang Shijie wrote: > In the real tests, there are maybe many times the cc->nr_migratepages is zero, > but isolate_migratepages() returns ISOLATE_SUCCESS. Odd choice of language. Are there or are there not many times that cc->nr_migratepages is zero? It does not affect the patch but it is a slightly confusing changelog. > In order to get better performance, we should check the number of the > really isolated pages. And do the optimazition for this case. > It's not critical for this patch but in the future it is preferred if the performance impact can be quantified if that is your justification for merging. I would expect the performance impact of this patch to be marginal. > Also fix the confused comments(from Mel Gorman). > > Tested this patch in MX6Q board. > > Signed-off-by: Huang Shijie Acked-by: Mel Gorman -- Mel Gorman SUSE Labs -- 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