From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f71.google.com (mail-oi0-f71.google.com [209.85.218.71]) by kanga.kvack.org (Postfix) with ESMTP id A33366B0003 for ; Tue, 17 Jul 2018 08:13:54 -0400 (EDT) Received: by mail-oi0-f71.google.com with SMTP id 22-v6so753988oix.0 for ; Tue, 17 Jul 2018 05:13:54 -0700 (PDT) Received: from mail-sor-f41.google.com (mail-sor-f41.google.com. [209.85.220.41]) by mx.google.com with SMTPS id a204-v6sor467012oif.12.2018.07.17.05.13.53 for (Google Transport Security); Tue, 17 Jul 2018 05:13:53 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20180717112515.GE7193@dhcp22.suse.cz> References: <20180712172942.10094-1-hannes@cmpxchg.org> <20180716155745.10368-1-drake@endlessm.com> <20180717112515.GE7193@dhcp22.suse.cz> From: Daniel Drake Date: Tue, 17 Jul 2018 07:13:52 -0500 Message-ID: Subject: Re: [PATCH 0/10] psi: pressure stall information for CPU, memory, and IO v2 Content-Type: text/plain; charset="UTF-8" Sender: owner-linux-mm@kvack.org List-ID: To: Michal Hocko Cc: hannes@cmpxchg.org, Linux Kernel , linux-mm@kvack.org, cgroups@vger.kernel.org, Linux Upstreaming Team , linux-block@vger.kernel.org, Ingo Molnar , Peter Zijlstra , Andrew Morton , Tejun Heo , Balbir Singh , Mike Galbraith , Oliver Yang , Shakeel Butt , xxx xxx , Taras Kondratiuk , Daniel Walker , Vinayak Menon , Ruslan Ruslichenko , kernel-team@fb.com On Tue, Jul 17, 2018 at 6:25 AM, Michal Hocko wrote: > Yes this is really unfortunate. One thing that could help would be to > consider a trashing level during the reclaim (get_scan_count) to simply > forget about LRUs which are constantly refaulting pages back. We already > have the infrastructure for that. We just need to plumb it in. Can you go into a bit more detail about that infrastructure and how we might detect which pages are being constantly refaulted? I'm interested in spending a few hours on this topic to see if I can come up with anything. Thanks Daniel