Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754055AbdCBDld (ORCPT ); Wed, 1 Mar 2017 22:41:33 -0500 Received: from out4441.biz.mail.alibaba.com ([47.88.44.41]:7758 "EHLO out4441.biz.mail.alibaba.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753838AbdCBDlV (ORCPT ); Wed, 1 Mar 2017 22:41:21 -0500 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R191e4;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e02c03306;MF=hillf.zj@alibaba-inc.com;NM=1;PH=DS;RN=8;SC=85;SR=0;TI=SMTPD_---.7jcLn1._1488425877; Reply-To: "Hillf Danton" From: "Hillf Danton" To: "'Johannes Weiner'" , "'Andrew Morton'" Cc: "'Jia He'" , "'Michal Hocko'" , "'Mel Gorman'" , , , References: <20170228214007.5621-1-hannes@cmpxchg.org> <20170228214007.5621-10-hannes@cmpxchg.org> In-Reply-To: <20170228214007.5621-10-hannes@cmpxchg.org> Subject: Re: [PATCH 9/9] mm: remove unnecessary back-off function when retrying page reclaim Date: Thu, 02 Mar 2017 11:37:57 +0800 Message-ID: <078401d29306$628fbe00$27af3a00$@alibaba-inc.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 14.0 Thread-Index: AQGushofxnzLnyVlk/YQjboYC5yEOwJr86M7obVIk3A= Content-Language: zh-cn Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 636 Lines: 16 On March 01, 2017 5:40 AM Johannes Weiner wrote: > > The backoff mechanism is not needed. If we have MAX_RECLAIM_RETRIES > loops without progress, we'll OOM anyway; backing off might cut one or > two iterations off that in the rare OOM case. If we have intermittent > success reclaiming a few pages, the backoff function gets reset also, > and so is of little help in these scenarios. > > We might want a backoff function for when there IS progress, but not > enough to be satisfactory. But this isn't that. Remove it. > > Signed-off-by: Johannes Weiner > --- Acked-by: Hillf Danton