Skip site navigation (1) Skip section navigation (2)

Re: Autovacuum versus rolled-back transactions

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Alvaro Herrera <alvherre(at)commandprompt(dot)com>
Cc: pgsql-hackers(at)postgresql(dot)org
Subject: Re: Autovacuum versus rolled-back transactions
Date: 2007-06-01 01:19:28
Message-ID: 15412.1180660768@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-hackers
Alvaro Herrera <alvherre(at)commandprompt(dot)com> writes:
> If we apply Heikki's idea of advancing OldestXmin, I think what we
> should do is grab the value from pgstats when vacuum starts, and each
> time we're going to advance OldestXmin, grab the value from pgstats
> again; accumulate the differences from the various pgstat grabs.  At the
> end we send the accumulated differences as the new dead tuple count.

Considering that each of those values will be up to half a second old,
I can hardly think that this will accomplish anything except to
introduce a great deal of noise ...

			regards, tom lane

In response to

Responses

pgsql-hackers by date

Next:From: Robert TreatDate: 2007-06-01 02:08:01
Subject: Re: table partitioning pl/pgsql helpers
Previous:From: ITAGAKI TakahiroDate: 2007-06-01 01:08:27
Subject: Re: Autovacuum versus rolled-back transactions

Privacy Policy | About PostgreSQL
Copyright © 1996-2014 The PostgreSQL Global Development Group