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

Re: BUG #5946: Long exclusive lock taken by vacuum (not full)

From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To: Robert Haas <robertmhaas(at)gmail(dot)com>
Cc: Greg Stark <gsstark(at)mit(dot)edu>, Alvaro Herrera <alvherre(at)commandprompt(dot)com>, Christopher Browne <cbbrowne(at)gmail(dot)com>, Maxim Boguk <maxim(dot)boguk(at)gmail(dot)com>, pgsql-bugs <pgsql-bugs(at)postgresql(dot)org>
Subject: Re: BUG #5946: Long exclusive lock taken by vacuum (not full)
Date: 2011-03-28 04:29:12
Message-ID: 18898.1301286552@sss.pgh.pa.us (view raw or flat)
Thread:
Lists: pgsql-bugs
Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> I think we've had a number of pieces of evidence that suggest that
> extending 8kB at a time is too costly, but I agree with Greg that the
> idea of extending an arbitrarily large table by 10% at a time is
> pretty frightening - that could involve allocating a gigantic amount
> of space on a big table.  I would be inclined to do something like
> extend by 10% of table or 1MB, whichever is smaller.

Sure, something like that sounds sane, though the precise numbers
need some validation.

> ... And a 1MB extension is probably also small enough
> that we can do it in the foreground without too much of a hiccup.

Less than convinced about this.

			regards, tom lane

In response to

Responses

pgsql-bugs by date

Next:From: Alvaro HerreraDate: 2011-03-28 10:26:49
Subject: Re: BUG #5946: Long exclusive lock taken by vacuum (not full)
Previous:From: Robert HaasDate: 2011-03-28 04:28:14
Subject: Re: BUG #5946: Long exclusive lock taken by vacuum (not full)

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