From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-oi0-f41.google.com (mail-oi0-f41.google.com [209.85.218.41]) by kanga.kvack.org (Postfix) with ESMTP id D39AD6B0257 for ; Mon, 23 Nov 2015 04:24:30 -0500 (EST) Received: by oige206 with SMTP id e206so116509450oig.2 for ; Mon, 23 Nov 2015 01:24:30 -0800 (PST) Received: from mail-oi0-x22a.google.com (mail-oi0-x22a.google.com. [2607:f8b0:4003:c06::22a]) by mx.google.com with ESMTPS id y6si7795241oei.53.2015.11.23.01.24.30 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 23 Nov 2015 01:24:30 -0800 (PST) Received: by oixx65 with SMTP id x65so116649451oix.0 for ; Mon, 23 Nov 2015 01:24:30 -0800 (PST) MIME-Version: 1.0 In-Reply-To: <5652CF40.6040400@intel.com> References: <20151119092920.GA11806@aaronlu.sh.intel.com> <564DCEA6.3000802@suse.cz> <564EDFE5.5010709@intel.com> <564EE8FD.7090702@intel.com> <564EF0B6.10508@suse.cz> <20151123081601.GA29397@js1304-P5Q-DELUXE> <5652CF40.6040400@intel.com> Date: Mon, 23 Nov 2015 18:24:29 +0900 Message-ID: Subject: Re: hugepage compaction causes performance drop From: Joonsoo Kim Content-Type: text/plain; charset=UTF-8 Sender: owner-linux-mm@kvack.org List-ID: To: Aaron Lu Cc: Joonsoo Kim , Vlastimil Babka , Linux Memory Management List , Huang Ying , Dave Hansen , Tim Chen , lkp@lists.01.org, Andrea Arcangeli , David Rientjes 2015-11-23 17:33 GMT+09:00 Aaron Lu : > On 11/23/2015 04:16 PM, Joonsoo Kim wrote: >> Numbers looks fine to me. I guess this performance degradation is >> caused by COMPACT_CLUSTER_MAX change (from 32 to 256). THP allocation >> is async so should be aborted quickly. But, after isolating 256 >> migratable pages, it can't be aborted and will finish 256 pages >> migration (at least, current implementation). Let me correct above comment. It can be aborted after some try. >> Aaron, please test again with setting COMPACT_CLUSTER_MAX to 32 >> (in swap.h)? > > This is what I found in include/linux/swap.h: > > #define SWAP_CLUSTER_MAX 32UL > #define COMPACT_CLUSTER_MAX SWAP_CLUSTER_MAX > > Looks like it is already 32, or am I looking at the wrong place? > > BTW, I'm using v4.3 for all these tests, and I just checked v4.4-rc2, > the above definition doesn't change. Sorry. I looked at linux-next tree and, there, it is 128. Please ignore my comment! :) >> >> And, please attach always-always's vmstat numbers, too. > > Sure, attached the vmstat tool output, taken every second. Oops... I'd like to see '1 sec interval cat /proc/vmstat' for always-never. Thanks. -- 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