Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756916AbcJSCiy (ORCPT ); Tue, 18 Oct 2016 22:38:54 -0400 Received: from sci-ig2.spreadtrum.com ([222.66.158.135]:38535 "EHLO SHSQR01.spreadtrum.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1756761AbcJSCiW (ORCPT ); Tue, 18 Oct 2016 22:38:22 -0400 Date: Wed, 19 Oct 2016 10:32:23 +0800 From: Ming Ling To: Michal Hocko CC: Minchan Kim , , , , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v2] mm: exclude isolated non-lru pages from NR_ISOLATED_ANON or NR_ISOLATED_FILE. Message-ID: <20161019023222.GA28651@spreadtrum.com> References: <20161014134604.GA2179@blaptop> <20161014135334.GF6063@dhcp22.suse.cz> <20161014144448.GA2899@blaptop> <20161014150355.GH6063@dhcp22.suse.cz> <20161014152633.GA3157@blaptop> <20161015071044.GC9949@dhcp22.suse.cz> <20161016230618.GB9196@bbox> <20161017084244.GF23322@dhcp22.suse.cz> <20161018062950.GA18818@bbox> <20161018125247.GI12092@dhcp22.suse.cz> MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20161018125247.GI12092@dhcp22.suse.cz> User-Agent: Mutt/1.5.21 (2010-09-15) X-MAIL: SHSQR01.spreadtrum.com u9J2bdU1040316 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2646 Lines: 61 二, 10月 18, 2016 at 02:52:47下午 +0200, Michal Hocko wrote: hi, > On Tue 18-10-16 15:29:50, Minchan Kim wrote: > > On Mon, Oct 17, 2016 at 10:42:45AM +0200, Michal Hocko wrote: > [...] > > > Sure, what do you think about the following? I haven't marked it for > > > stable because there was no bug report for it AFAIU. > > > --- > > > From 3b2bd4486f36ada9f6dc86d3946855281455ba9f Mon Sep 17 00:00:00 2001 > > > From: Ming Ling > > > Date: Mon, 17 Oct 2016 10:26:50 +0200 > > > Subject: [PATCH] mm, compaction: fix NR_ISOLATED_* stats for pfn based > > > migration > > > > > > Since bda807d44454 ("mm: migrate: support non-lru movable page > > > migration") isolate_migratepages_block) can isolate !PageLRU pages which > > > would acct_isolated account as NR_ISOLATED_*. Accounting these non-lru > > > pages NR_ISOLATED_{ANON,FILE} doesn't make any sense and it can misguide > > > heuristics based on those counters such as pgdat_reclaimable_pages resp. > > > too_many_isolated which would lead to unexpected stalls during the > > > direct reclaim without any good reason. Note that > > > __alloc_contig_migrate_range can isolate a lot of pages at once. > > > > > > On mobile devices such as 512M ram android Phone, it may use a big zram > > > swap. In some cases zram(zsmalloc) uses too many non-lru but migratedable > > > pages, such as: > > > > > > MemTotal: 468148 kB > > > Normal free:5620kB > > > Free swap:4736kB > > > Total swap:409596kB > > > ZRAM: 164616kB(zsmalloc non-lru pages) > > > active_anon:60700kB > > > inactive_anon:60744kB > > > active_file:34420kB > > > inactive_file:37532kB > > > > > > Fix this by only accounting lru pages to NR_ISOLATED_* in > > > isolate_migratepages_block right after they were isolated and we still > > > know they were on LRU. Drop acct_isolated because it is called after the > > > fact and we've lost that information. Batching per-cpu counter doesn't > > > make much improvement anyway. Also make sure that we uncharge only LRU > > > pages when putting them back on the LRU in putback_movable_pages resp. > > > when unmap_and_move migrates the page. > > > > > > Fixes: bda807d44454 ("mm: migrate: support non-lru movable page migration") > > > Signed-off-by: Ming Ling > > > Signed-off-by: Michal Hocko > > > > Acked-by: Minchan Kim > > > > with folding other fix patch you posted. > > Thanks. > > Ming, are you OK with this patch? Can I post it to Andrew? > -- I think that's fine. Just do it. Thank you. > Michal Hocko > SUSE Labs