From: Tom Lane <tgl@sss.pgh.pa.us>
To: Dilip Kumar <dilipbalaut@gmail.com>
cc: Andres Freund <andres@anarazel.de>, Justin Pryzby <pryzby@telsasoft.com>,
        Robert Haas <robertmhaas@gmail.com>,
        Ashutosh Sharma <ashu.coek88@gmail.com>,
        Maciek Sakrejda <m.sakrejda@gmail.com>,
        Bruce Momjian <bruce@momjian.us>,
        Alvaro Herrera <alvherre@alvh.no-ip.org>,
        Andrew Dunstan <andrew@dunslane.net>,
        Heikki Linnakangas <hlinnaka@iki.fi>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: [Proposal] Fully WAL logged CREATE DATABASE - No Checkpoints
In-reply-to: 
 <CAFiTN-uZjJn+SN0p1t2CNh+u8xSdetKZuGdnHT14uyJMbDqiww@mail.gmail.com>
References: 
 <CA+TgmobUW9NQK7EJkV_0F87bqqq5BSHKiX2+wfthLcy4qA7YvQ@mail.gmail.com>
 <20220802175043.GA13682@telsasoft.com>
 <CA+TgmobZufK6PcCRpvjP6dJqOBO-woWZF0cqMHWGvzkbgeaBKw@mail.gmail.com>
 <2767668.1659476794@sss.pgh.pa.us> <20220802220416.GC13682@telsasoft.com>
 <20220802222334.umf5wsa2r63koppn@awork3.anarazel.de>
 <CAFiTN-sG9-ocJFN+KBAQ2mTuF-9Ja+i1Qo81yqr0WDOsqqYpLg@mail.gmail.com>
 <CAFiTN-sL8M+Z6nongs=rSqfP26Vr0O_EYLfcwbO-Emz1GYxtxA@mail.gmail.com>
 <CAFiTN-v4u2WJT6y1n4wtM4Z3tffJonT7zuRKegYao9p-Oyb07Q@mail.gmail.com>
 <CAFiTN-thCGvRF0_WftbDc0KFagB3vgHHGrpNdRMJ6vtkObEMoA@mail.gmail.com>
 <20220804212932.xyxzeprxvcnukg7o@awork3.anarazel.de>
 <CAFiTN-t5aePMKYPLica9_qbP78w3YUWO4OaE7E_bsYhUpXEu2g@mail.gmail.com>
 <CAFiTN-uZjJn+SN0p1t2CNh+u8xSdetKZuGdnHT14uyJMbDqiww@mail.gmail.com>
Comments: In-reply-to Dilip Kumar <dilipbalaut@gmail.com>
	message dated "Fri, 05 Aug 2022 12:32:39 +0530"
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-ID: <102025.1659802004.1@sss.pgh.pa.us>
Date: Sat, 06 Aug 2022 12:06:44 -0400
Message-ID: <102026.1659802004@sss.pgh.pa.us>
Archived-At: 
 <https://www.postgresql.org/message-id/102026.1659802004%40sss.pgh.pa.us>
Precedence: bulk

Dilip Kumar <dilipbalaut@gmail.com> writes:
> On Fri, Aug 5, 2022 at 10:43 AM Dilip Kumar <dilipbalaut@gmail.com> wrote:
>> Yeah maybe it is not necessary to close as these unowned smgr will
>> automatically get closed on the transaction end.

I do not think this is a great idea for the per-relation smgrs created
during RelationCopyStorageUsingBuffer.  Yeah, they'll be mopped up at
transaction end, but that doesn't mean that creating possibly tens of
thousands of transient smgrs isn't going to cause performance issues.

I think RelationCopyStorageUsingBuffer needs to open and then close
the smgrs it uses, which means that ReadBufferWithoutRelcache is not the
appropriate API for it to use, either; need to go down another level.

			regards, tom lane