Horton

Re: autovacuum not prioritising for-wraparound tables

Jeff Janes <jeff.janes@gmail.com>

View thread View on postgr.es
From: Jeff Janes <jeff.janes@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Andres Freund <andres@2ndquadrant.com>, Tom Lane <tgl@sss.pgh.pa.us>, Alvaro Herrera <alvherre@2ndquadrant.com>, Christopher Browne <cbbrowne@gmail.com>, Heikki Linnakangas <hlinnakangas@vmware.com>, Pg Hackers <pgsql-hackers@postgresql.org>
Date: 2013-01-27T19:33:18Z
Lists: pgsql-hackers 
On Fri, Jan 25, 2013 at 10:02 AM, Robert Haas <robertmhaas@gmail.com> wrote:
>
> I'm worried about the case of a very, very frequently updated table
> getting put ahead of a table that needs a wraparound vacuum, but only
> just.  It doesn't sit well with me to think that the priority of that
> goes from 0 (we don't even try to update it) to infinity (it goes
> ahead of all tables needing to be vacuumed for dead tuples) the
> instant we hit the vacuum_freeze_table_age.

What if it were the instant we hit autovacuum_freeze_max_age, not
vacuum_freeze_table_age?  Or does the current behavior already do
this?  Which process is responsible for enforcing
autovacuum_freeze_max_age?


Cheers,

Jeff

Commits

  1. COPY FREEZE and mark committed on fresh tables.

  2. Add vacuum_freeze_table_age GUC option, to control when VACUUM should