From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wi0-f169.google.com (mail-wi0-f169.google.com [209.85.212.169]) by kanga.kvack.org (Postfix) with ESMTP id 809E56B0038 for ; Thu, 20 Aug 2015 10:25:32 -0400 (EDT) Received: by wicja10 with SMTP id ja10so37763413wic.1 for ; Thu, 20 Aug 2015 07:25:32 -0700 (PDT) Received: from mail-wi0-f181.google.com (mail-wi0-f181.google.com. [209.85.212.181]) by mx.google.com with ESMTPS id er10si12945524wib.87.2015.08.20.07.25.30 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 20 Aug 2015 07:25:31 -0700 (PDT) Received: by wicja10 with SMTP id ja10so37762846wic.1 for ; Thu, 20 Aug 2015 07:25:30 -0700 (PDT) Date: Thu, 20 Aug 2015 16:25:29 +0200 From: Michal Hocko Subject: Re: [PATCH 03/10] mm, page_alloc: Remove unnecessary recalculations for dirty zone balancing Message-ID: <20150820142529.GJ20110@dhcp22.suse.cz> References: <1439376335-17895-1-git-send-email-mgorman@techsingularity.net> <1439376335-17895-4-git-send-email-mgorman@techsingularity.net> <20150820124526.GE20110@dhcp22.suse.cz> <20150820134526.GD12432@techsingularity.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150820134526.GD12432@techsingularity.net> Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Linux-MM , Johannes Weiner , Rik van Riel , Vlastimil Babka , David Rientjes , Joonsoo Kim , LKML On Thu 20-08-15 14:45:26, Mel Gorman wrote: > On Thu, Aug 20, 2015 at 02:45:27PM +0200, Michal Hocko wrote: > > On Wed 12-08-15 11:45:28, Mel Gorman wrote: > > > File-backed pages that will be immediately are balanced between zones but > > ^written to... > > > > > it's unnecessarily expensive. > > > > to do WHAT? I guess you meant checking gfp_mask resp. alloc_mask? I > > doubt it would make a noticeable difference as this is a slow path > > already but I agree it doesn't make sense to check it again. > > > > File-backed pages that will be immediately written are balanced between > zones. This heuristic tries to avoid having a single zone filled with > recently dirtied pages but the checks are unnecessarily expensive. Move > consider_zone_balanced into the alloc_context instead of checking bitmaps > multiple times. The patch also gives the parameter a more meaningful name. Sounds much better. Thanks! -- Michal Hocko 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/ . Don't email: email@kvack.org