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[86.49.243.43]) by smtp.gmail.com with ESMTPSA id t17sm28870320wrr.26.2019.04.10.02.13.28 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Wed, 10 Apr 2019 02:13:28 -0700 (PDT) Date: Wed, 10 Apr 2019 11:13:27 +0200 From: Tomas Vondra To: Kyotaro HORIGUCHI Cc: andres@anarazel.de, a.zakirov@postgrespro.ru, alvherre@2ndquadrant.com, ah@cybertec.at, magnus@hagander.net, robertmhaas@gmail.com, tgl@sss.pgh.pa.us, pgsql-hackers@postgresql.org Subject: Re: shared-memory based stats collector Message-ID: <20190410091327.fpnvjbuu74dzxizl@development> References: <20190403195659.fcmk2i7ruxhtyqjl@alap3.anarazel.de> <20190404.092512.142064795.horiguchi.kyotaro@lab.ntt.co.jp> <20190409150333.5iashyjxm5jmraml@development> <20190410.093929.123264423.horiguchi.kyotaro@lab.ntt.co.jp> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Disposition: inline In-Reply-To: <20190410.093929.123264423.horiguchi.kyotaro@lab.ntt.co.jp> User-Agent: NeoMutt/20180716-1444-295967 List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Precedence: bulk On Wed, Apr 10, 2019 at 09:39:29AM +0900, Kyotaro HORIGUCHI wrote: >At Tue, 9 Apr 2019 17:03:33 +0200, Tomas Vondra wrote in <20190409150333.5iashyjxm5jmraml@development> >> Unfortunately, now that we're past code freeze it's clear this is a >> PG12 >> matter now :-( >> >> I personally consider this to be very worthwhile & beneficial >> improvement, >> but I agree with Andres the patch did not quite get to committable >> state >> in the last CF. Conidering how sensitive part it touches, I suggest we >> try >> to get it committed early in the PG13 cycle. I'm willing to spend some >> time on doing test/benchmarks and reviewing the code, if needed. > >I'm very happy to be told that. Actually the code was a rush work >(mainly for reverting refactoring) and left some stupid >mistakes. I'm going through on the patch again and polish code. > While reviewing the patch I've always had issue with evaluating how it behaves for various scenarios / workloads. The reviews generally did one specific benchmark, but I find that unsatisfactory. I wonder whether if we could develop a small set of more comprehensive workloads for this patch (i.e. different numbers of objects, access patterns, ...). regards -- Tomas Vondra http://www.2ndQuadrant.com PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services