From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752380AbcGVQCT (ORCPT ); Fri, 22 Jul 2016 12:02:19 -0400 Received: from gum.cmpxchg.org ([85.214.110.215]:54144 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751244AbcGVQCS (ORCPT ); Fri, 22 Jul 2016 12:02:18 -0400 Date: Fri, 22 Jul 2016 12:02:12 -0400 From: Johannes Weiner To: Mel Gorman Cc: Andrew Morton , Minchan Kim , Michal Hocko , Vlastimil Babka , Linux-MM , LKML Subject: Re: [PATCH 5/5] mm, vmscan: Account for skipped pages as a partial scan Message-ID: <20160722160212.GE23650@cmpxchg.org> References: <1469110261-7365-1-git-send-email-mgorman@techsingularity.net> <1469110261-7365-6-git-send-email-mgorman@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1469110261-7365-6-git-send-email-mgorman@techsingularity.net> User-Agent: Mutt/1.6.2 (2016-07-01) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jul 21, 2016 at 03:11:01PM +0100, Mel Gorman wrote: > Page reclaim determines whether a pgdat is unreclaimable by examining how > many pages have been scanned since a page was freed and comparing that to > the LRU sizes. Skipped pages are not reclaim candidates but contribute to > scanned. This can prematurely mark a pgdat as unreclaimable and trigger > an OOM kill. > > This patch accounts for skipped pages as a partial scan so that an > unreclaimable pgdat will still be marked as such but by scaling the cost > of a skip, it'll avoid the pgdat being marked prematurely. > > Signed-off-by: Mel Gorman Acked-by: Johannes Weiner