Received: from malur.postgresql.org ([217.196.149.56])
	by arkaria.postgresql.org with esmtps
 (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1jYsed-00067a-Ld
	for pgsql-hackers@arkaria.postgresql.org; Wed, 13 May 2020 14:46:39 +0000
Received: from localhost ([127.0.0.1] helo=malur.postgresql.org)
	by malur.postgresql.org with esmtp (Exim 4.92)
	(envelope-from <pgsql-hackers-owner+archive@lists.postgresql.org>)
	id 1jYsec-00080k-JU
	for pgsql-hackers@arkaria.postgresql.org; Wed, 13 May 2020 14:46:38 +0000
Received: from makus.postgresql.org ([2001:4800:3e1:1::229])
	by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <masao.fujii@oss.nttdata.com>)
	id 1jYsec-00080d-CW
	for pgsql-hackers@lists.postgresql.org; Wed, 13 May 2020 14:46:38 +0000
Received: from oss.nttdata.com ([49.212.34.109])
	by makus.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256)
	(Exim 4.92)
	(envelope-from <masao.fujii@oss.nttdata.com>)
	id 1jYseZ-0004RT-3q
	for pgsql-hackers@postgresql.org; Wed, 13 May 2020 14:46:37 +0000
Received: from hnk.local (p2358024-ipbf2221funabasi.chiba.ocn.ne.jp
 [114.177.56.24])
	by oss.nttdata.com (Postfix) with ESMTPSA id CF17060172;
	Wed, 13 May 2020 23:46:30 +0900 (JST)
X-Virus-Status: Clean
X-Virus-Scanned: clamav-milter 0.102.2 at oss.nttdata.com
Subject: Re: SLRU statistics
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>,
 Alvaro Herrera <alvherre@2ndquadrant.com>,
 Masahiko Sawada <masahiko.sawada@2ndquadrant.com>,
 "tsunakawa.takay@fujitsu.com" <tsunakawa.takay@fujitsu.com>,
 "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>
References: <20200402004136.wodwftan45mcwggm@development>
 <f02fd0ec-a240-b5bf-9992-5faf582738f1@oss.nttdata.com>
 <20200430181901.24tlriahmafi4sfn@development>
 <0e1c8904-13be-ab70-0096-54f0b30e43ba@oss.nttdata.com>
 <20200502000818.nn4kpewiput42bnb@development>
 <49b8ad17-f6d9-a086-a952-ff1fec3ac1b3@oss.nttdata.com>
 <20200502105500.hwhba3d6s3hlrqf6@development>
 <20200502165905.brfxv6dk5vjdbgti@development>
 <976bbb73-a112-de3c-c488-b34b64609793@oss.nttdata.com>
 <b8784fe6-1401-ab35-aa14-d57b5bb8e312@oss.nttdata.com>
 <20200513082159.myflgcs5fnhnujbk@development>
 <b407746a-4fb6-7128-9391-c3765eb44718@oss.nttdata.com>
 <32135.1589379999@sss.pgh.pa.us>
From: Fujii Masao <masao.fujii@oss.nttdata.com>
Message-ID: <fe3332c8-485a-540b-ca34-b024d452a7ae@oss.nttdata.com>
Date: Wed, 13 May 2020 23:46:30 +0900
User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:68.0)
 Gecko/20100101 Thunderbird/68.8.0
MIME-Version: 1.0
In-Reply-To: <32135.1589379999@sss.pgh.pa.us>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
List-Id: <pgsql-hackers.lists.postgresql.org>
List-Help: <https://lists.postgresql.org/manage/>
List-Subscribe: <https://lists.postgresql.org/manage/>
List-Post: <mailto:pgsql-hackers@lists.postgresql.org>
List-Owner: <mailto:pgsql-hackers-owner@lists.postgresql.org>
List-Archive: <https://www.postgresql.org/list/pgsql-hackers>
Precedence: bulk



On 2020/05/13 23:26, Tom Lane wrote:
> Fujii Masao <masao.fujii@oss.nttdata.com> writes:
>> On 2020/05/13 17:21, Tomas Vondra wrote:
>>> On Wed, May 13, 2020 at 04:10:30PM +0900, Fujii Masao wrote:
>>>> Also I found another minor issue; SLRUStats has not been initialized to 0
>>>> and which could update the counters unexpectedly. Attached patch fixes
>>>> this issue.
> 
>> Pushed both. Thanks!
> 
> Why is that necessary?  A static variable is defined by C to start off
> as zeroes.

Because SLRUStats is not a static variable. No?

Regards,

-- 
Fujii Masao
Advanced Computing Technology Center
Research and Development Headquarters
NTT DATA CORPORATION