From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754364AbaIXPOd (ORCPT ); Wed, 24 Sep 2014 11:14:33 -0400 Received: from mx2.parallels.com ([199.115.105.18]:56207 "EHLO mx2.parallels.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751534AbaIXPO3 (ORCPT ); Wed, 24 Sep 2014 11:14:29 -0400 Date: Wed, 24 Sep 2014 19:14:21 +0400 From: Vladimir Davydov To: Johannes Weiner CC: Andrew Morton , Greg Thelen , Dave Hansen , Michal Hocko , , , Subject: Re: [patch 2/3] mm: memcontrol: simplify detecting when the memory+swap limit is hit Message-ID: <20140924151421.GA29445@esperanza> References: <1411571338-8178-1-git-send-email-hannes@cmpxchg.org> <1411571338-8178-3-git-send-email-hannes@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Disposition: inline In-Reply-To: <1411571338-8178-3-git-send-email-hannes@cmpxchg.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 24, 2014 at 11:08:57AM -0400, Johannes Weiner wrote: > When attempting to charge pages, we first charge the memory counter > and then the memory+swap counter. If one of the counters is at its > limit, we enter reclaim, but if it's the memory+swap counter, reclaim > shouldn't swap because that wouldn't change the situation. However, > if the counters have the same limits, we never get to the memory+swap > limit. To know whether reclaim should swap or not, there is a state > flag that indicates whether the limits are equal and whether hitting > the memory limit implies hitting the memory+swap limit. > > Just try the memory+swap counter first. > > Signed-off-by: Johannes Weiner Reviewed-by: Vladimir Davydov