Re: Automatic free space map filling - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: Automatic free space map filling
Date
Msg-id 200604281958.k3SJwGg07888@candle.pha.pa.us
Whole thread Raw
In response to Re: Automatic free space map filling  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Automatic free space map filling
Re: Automatic free space map filling
List pgsql-hackers
Tom Lane wrote:
> Alvaro Herrera <alvherre@commandprompt.com> writes:
> > So for you it would certainly help a lot to be able to vacuum the first
> > X pages of the big table, stop, release locks, create new transaction,
> > continue with the next X pages, lather, rinse, repeat.
> 
> > This is perfectly doable, it only needs enough motivation from a
> > knowledgeable person.
> 
> Bruce and I were discussing this the other day; it'd be pretty easy to
> make plain VACUUM start a fresh transaction immediately after it
> finishes a scan heap/clean indexes/clean heap cycle.  The infrastructure
> for this (in particular, session-level locks that won't be lost by
> closing the xact) is all there.  You'd have to figure out how often to
> start a new xact ... every cycle is probably too often, at least for
> smaller maintenance_work_mem settings ... but it'd not be hard or
> involve any strange changes in system semantics.

Should this be a TODO?  One item of discussion was taht people should
just increase their workmem so the job can be done faster in larger
batches.


--  Bruce Momjian   http://candle.pha.pa.us EnterpriseDB    http://www.enterprisedb.com
 + If your life is a hard drive, Christ can be your backup. +


pgsql-hackers by date:

Previous
From: "Brandon Black"
Date:
Subject: Re: Constraint Exclusion + Joins?
Next
From: Robert Treat
Date:
Subject: Re: Logging pg_autovacuum