Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753286AbdDMQD4 (ORCPT ); Thu, 13 Apr 2017 12:03:56 -0400 Received: from gum.cmpxchg.org ([85.214.110.215]:45336 "EHLO gum.cmpxchg.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752688AbdDMQDy (ORCPT ); Thu, 13 Apr 2017 12:03:54 -0400 Date: Thu, 13 Apr 2017 12:03:43 -0400 From: Johannes Weiner To: Shakeel Butt Cc: Tim Murray , Michal Hocko , Vladimir Davydov , LKML , cgroups@vger.kernel.org, Linux MM , surenb@google.com, totte@google.com, kernel-team@android.com Subject: Re: [RFC 0/1] add support for reclaiming priorities per mem cgroup Message-ID: <20170413160343.GC29727@cmpxchg.org> References: <20170317231636.142311-1-timmurray@google.com> <20170330155123.GA3929@cmpxchg.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.8.0 (2017-02-23) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 927 Lines: 18 On Thu, Mar 30, 2017 at 09:48:55AM -0700, Shakeel Butt wrote: > > A more useful metric for memory pressure at this point is quantifying > > that time you spend thrashing: time the job spends in direct reclaim > > and on the flipside time the job waits for recently evicted pages to > > come back. Combined, that gives you a good measure of overhead from > > memory pressure; putting that in relation to a useful baseline of > > meaningful work done gives you a portable scale of how effictively > > your job is running. > > > > I'm working on that right now, hopefully I'll have something useful > > soon. > > Johannes, is the work you are doing only about file pages or will it > equally apply to anon pages as well? It will work on both, with the caveat that *any* swapin is counted as memory delay, whereas only cache misses of recently evicted entries count toward it (we don't have timestamped shadow entries for anon).