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=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,UNPARSEABLE_RELAY,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by aws-us-west-2-korg-lkml-1.web.codeaurora.org (Postfix) with ESMTP id 67680C5CFC0 for ; Fri, 15 Jun 2018 00:23:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D523E208D7 for ; Fri, 15 Jun 2018 00:23:39 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D523E208D7 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.alibaba.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965247AbeFOAXh (ORCPT ); Thu, 14 Jun 2018 20:23:37 -0400 Received: from out30-132.freemail.mail.aliyun.com ([115.124.30.132]:45105 "EHLO out30-132.freemail.mail.aliyun.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965143AbeFOAXg (ORCPT ); Thu, 14 Jun 2018 20:23:36 -0400 X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R691e4;CH=green;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e01429;MF=yang.shi@linux.alibaba.com;NM=1;PH=DS;RN=6;SR=0;TI=SMTPD_---0T2mKbdF_1529022207; Received: from US-143344MP.local(mailfrom:yang.shi@linux.alibaba.com fp:SMTPD_---0T2mKbdF_1529022207) by smtp.aliyun-inc.com(127.0.0.1); Fri, 15 Jun 2018 08:23:29 +0800 Subject: Re: [PATCH] doc: add description to dirtytime_expire_seconds To: tytso@mit.edu, corbet@lwn.net, akpm@linux-foundation.org Cc: linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <1527724613-17768-1-git-send-email-yang.shi@linux.alibaba.com> From: Yang Shi Message-ID: Date: Thu, 14 Jun 2018 17:23:25 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.12; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <1527724613-17768-1-git-send-email-yang.shi@linux.alibaba.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Content-Language: en-US Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ping Ted, Any comment is appreciated. Regards, Yang On 5/30/18 4:56 PM, Yang Shi wrote: > commit 1efff914afac8a965ad63817ecf8861a927c2ace ("fs: add > dirtytime_expire_seconds sysctl") introduced dirtytime_expire_seconds > knob, but there is not description about it in > Documentation/sysctl/vm.txt. > > Add the description for it. > > Cc: Theodore Ts'o > Signed-off-by: Yang Shi > --- > I didn't dig into the old review discussion about why the description > was not added at the first place. I'm supposed every knob under /proc/sys > should have a brief description. > > Documentation/sysctl/vm.txt | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt > index 17256f2..f4f4f9c 100644 > --- a/Documentation/sysctl/vm.txt > +++ b/Documentation/sysctl/vm.txt > @@ -27,6 +27,7 @@ Currently, these files are in /proc/sys/vm: > - dirty_bytes > - dirty_expire_centisecs > - dirty_ratio > +- dirtytime_expire_seconds > - dirty_writeback_centisecs > - drop_caches > - extfrag_threshold > @@ -178,6 +179,16 @@ The total available memory is not equal to total system memory. > > ============================================================== > > +dirtytime_expire_seconds > + > +When a lazytime inode is constantly having its pages dirtied, it with an > +updated timestamp will never get chance to be written out. This tunable > +is used to define when dirty inode is old enough to be eligible for > +writeback by the kernel flusher threads. And, it is also used as the > +interval to wakeup dirtytime_writeback thread. It is expressed in seconds. > + > +============================================================== > + > dirty_writeback_centisecs > > The kernel flusher threads will periodically wake up and write `old' data