From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with SMTP id 56E0C6B0047 for ; Sun, 28 Feb 2010 12:49:28 -0500 (EST) Message-ID: <4B8AAC9A.10203@redhat.com> Date: Sun, 28 Feb 2010 12:49:14 -0500 From: Rik van Riel MIME-Version: 1.0 Subject: Re: mm: used-once mapped file page detection References: <1266868150-25984-1-git-send-email-hannes@cmpxchg.org> <20100224133946.a5092804.akpm@linux-foundation.org> <20100226143232.GA13001@cmpxchg.org> In-Reply-To: <20100226143232.GA13001@cmpxchg.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Johannes Weiner Cc: Andrew Morton , KOSAKI Motohiro , Minchan Kim , linux-mm@kvack.org, linux-kernel@vger.kernel.org List-ID: On 02/26/2010 09:32 AM, Johannes Weiner wrote: > On Wed, Feb 24, 2010 at 01:39:46PM -0800, Andrew Morton wrote: >> On Mon, 22 Feb 2010 20:49:07 +0100 Johannes Weiner wrote: >> >>> This patch makes the VM be more careful about activating mapped file >>> pages in the first place. The minimum granted lifetime without >>> another memory access becomes an inactive list cycle instead of the >>> full memory cycle, which is more natural given the mentioned loads. >> >> iirc from a long time ago, the insta-activation of mapped pages was >> done because people were getting peeved about having their interactive >> applications (X, browser, etc) getting paged out, and bumping the pages >> immediately was found to help with this subjective problem. >> >> So it was a latency issue more than a throughput issue. I wouldn't be >> surprised if we get some complaints from people for the same reasons as >> a result of this patch. > > Agreed. Although we now have other things in place to protect them once > they are active (VM_EXEC protection, lazy active list scanning). You think we'll need VM_EXEC protection on the inactive list after your changes? -- 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