From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.5 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id CCE60CA9EA0 for ; Fri, 25 Oct 2019 21:25:32 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 86C4B21872 for ; Fri, 25 Oct 2019 21:25:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="vBxLZda3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 86C4B21872 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 0614B6B0003; Fri, 25 Oct 2019 17:25:32 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 011AA6B0006; Fri, 25 Oct 2019 17:25:31 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id E69146B0007; Fri, 25 Oct 2019 17:25:31 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0165.hostedemail.com [216.40.44.165]) by kanga.kvack.org (Postfix) with ESMTP id C019A6B0003 for ; Fri, 25 Oct 2019 17:25:31 -0400 (EDT) Received: from smtpin21.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with SMTP id 7C3C0909F for ; Fri, 25 Oct 2019 21:25:31 +0000 (UTC) X-FDA: 76083588462.21.part12_6a645cbc6a657 X-HE-Tag: part12_6a645cbc6a657 X-Filterd-Recvd-Size: 3127 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf15.hostedemail.com (Postfix) with ESMTP for ; Fri, 25 Oct 2019 21:25:30 +0000 (UTC) Received: from localhost.localdomain (c-73-231-172-41.hsd1.ca.comcast.net [73.231.172.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 537C92084C; Fri, 25 Oct 2019 21:25:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1572038729; bh=kEfjHO6oNibA4rpD7BZt5/bc6vP5kbCOVkqfe8i1laE=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=vBxLZda3SmNmIzubNaJAHWdryG5otSiXjxJo39W1tZUQUwHG1J/Udt9gww0bvwi7G G20Cp/tzU39paZxYD6ka53naYFEFeBbM3G+JOrzkw5m9FeIWxtWzMqHgTncMl0aEhK OsRipbz7jkiF7DWKiv5fEfAk2WRjMnKGDvTKnpeU= Date: Fri, 25 Oct 2019 14:25:28 -0700 From: Andrew Morton To: Qian Cai Cc: Michal Hocko , Mel Gorman , Waiman Long , Johannes Weiner , Roman Gushchin , Vlastimil Babka , Konstantin Khlebnikov , Jann Horn , Song Liu , Greg Kroah-Hartman , Rafael Aquini , linux-mm@kvack.org, LKML , Michal Hocko Subject: Re: [PATCH 2/2] mm, vmstat: reduce zone->lock holding time by /proc/pagetypeinfo Message-Id: <20191025142528.366148a0ffadf80946d62bbb@linux-foundation.org> In-Reply-To: <192965B3-B446-499C-AEE8-DFF087D46B87@lca.pw> References: <192965B3-B446-499C-AEE8-DFF087D46B87@lca.pw> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, 25 Oct 2019 07:18:37 -0400 Qian Cai wrote: > =EF=BB=BF >=20 > > On Oct 25, 2019, at 3:26 AM, Michal Hocko wrote: > >=20 > > Considering the pagetypeinfo is a debugging tool we do not really nee= d > > exact numbers here. The primary reason to look at the outuput is to s= ee > > how pageblocks are spread among different migratetypes and low number= of > > pages is much more interesting therefore putting a bound on the numbe= r > > of pages on the free_list sounds like a reasonable tradeoff. > >=20 > > The new output will simply tell > > [...] > > Node 6, zone Normal, type Movable >100000 >100000 >100000 >= 100000 41019 31560 23996 10054 3229 983 648 >=20 > It was mentioned that developers could use this file is to see the move= ment of those numbers for debugging, so this supposed to introduce regres= sions as there is no movement anymore for those 100k+ items? There are risks, but we have to do something! I'd be inclined to remove the ">" though - that'll unnecessarily break code which parses this data. otoh, maybe that's a feature: breaking those parsers will alert people to go in and find out what changed.