Horton

Re: Re: reloption to prevent VACUUM from truncating empty pages at the end of relation

Julien Rouhaud <rjuju123@gmail.com>

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From: Julien Rouhaud <rjuju123@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Masahiko Sawada <sawada.mshk@gmail.com>, "Tsunakawa, Takayuki" <tsunakawa.takay@jp.fujitsu.com>, Fujii Masao <masao.fujii@gmail.com>, David Steele <david@pgmasters.net>, Andres Freund <andres@anarazel.de>, "Bossart, Nathan" <bossartn@amazon.com>, Tom Lane <tgl@sss.pgh.pa.us>, Andrew Dunstan <andrew.dunstan@2ndquadrant.com>, Alvaro Herrera <alvherre@2ndquadrant.com>, Michael Paquier <michael@paquier.xyz>, Laurenz Albe <laurenz.albe@cybertec.at>, "Jamison, Kirk" <k.jamison@jp.fujitsu.com>, Amit Kapila <amit.kapila16@gmail.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2019-04-05T18:11:38Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Add TRUNCATE parameter to VACUUM.

  2. Add vacuum_truncate reloption.

  3. Allow VACUUM to be run with index cleanup disabled.

On Fri, Apr 5, 2019 at 7:04 PM Robert Haas <robertmhaas@gmail.com> wrote:
>
> On Thu, Apr 4, 2019 at 9:19 PM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> > As INDEX_CLEANUP option has been added by commit a96c41f, the new
> > option for this feature could also accept zero or one boolean
> > argument, that is SHRINK_TABLE [true|false] and true by default.
> > Explicit options on VACUUM command overwrite options set by
> > reloptions. And if the boolean argument is omitted the option depends
> > on the reloptions.
>
> Yes, I think that's how it should work, because that's how the other
> option works, and there's no compelling reason to be consistent.

Indeed, I totally agree.

> My preference is for "truncate" over "shrink".

I don't really like "shrink" either, but users already have problems
to get the difference between VACUUM and VACUUM FULL, I'm afraid that
"VACUUM TRUNCATE_TABLE" will just make things worse.