Re: New vacuum option to do only freezing - Mailing list pgsql-hackers

From Masahiko Sawada
Subject Re: New vacuum option to do only freezing
Date
Msg-id CAD21AoCn03NJWWZ3hwxkLZk+u8xRrDk3FXHpwOwHFr=pUpipBQ@mail.gmail.com
Whole thread Raw
In response to Re: New vacuum option to do only freezing  (Robert Haas <robertmhaas@gmail.com>)
Responses Re: New vacuum option to do only freezing  ("Bossart, Nathan" <bossartn@amazon.com>)
Re: New vacuum option to do only freezing  (Robert Haas <robertmhaas@gmail.com>)
List pgsql-hackers
On Fri, Nov 2, 2018 at 2:02 AM Robert Haas <robertmhaas@gmail.com> wrote:
>
> On Mon, Oct 1, 2018 at 6:23 AM Masahiko Sawada <sawada.mshk@gmail.com> wrote:
> > Attached patch adds a new option FREEZE_ONLY to VACUUM command. This
> > option is same as FREEZE option except for it disables reclaiming dead
> > tuples. That is, with this option vacuum does pruning HOT chain,
> > freezing live tuples and maintaining both visibility map and freespace
> > map but does not collect dead tuples and invoke neither heap vacuum
> > nor index vacuum. This option will be useful if user wants to prevent
> > XID wraparound a table as quick as possible, especially when table is
> > quite large and is about to XID wraparound. I think this usecase was
> > mentioned in some threads but I couldn't find them.
>

Thank you for the comment!

> The feature seems like a reasonable one, but the name doesn't seem
> like a good choice.  It doesn't only freeze - e.g. it HOT-prunes, as
> it must.  Maybe consider something like (without_index_cleanup true)
> or (index_cleanup false).

Adding a field-and-value style option might be worth. Or maybe we can
add one option for example freeze_without_index_cleanup?

Regards,

--
Masahiko Sawada
NIPPON TELEGRAPH AND TELEPHONE CORPORATION
NTT Open Source Software Center


pgsql-hackers by date:

Previous
From: Masahiko Sawada
Date:
Subject: Re: New vacuum option to do only freezing
Next
From: LAM JUN RONG
Date:
Subject: RE: [PATCH] Improvements to "Getting started" tutorial for GoogleCode-in task