From: Robert Haas <robertmhaas@gmail.com>
To: Laszlo Nagy <gandalf@shopzeus.com>
Cc: pgsql-performance@postgresql.org <pgsql-performance@postgresql.org>
Subject: Re: Big index sizes
Date: Tue, 30 Dec 2008 09:43:28 -0500
Message-ID: <603c8f070812300643n3bcc0454j2022d4efaa6122d5@mail.gmail.com> (raw)
In-Reply-To: <4959E477.9050700@shopzeus.com>
References: <4959E477.9050700@shopzeus.com>
On Tue, Dec 30, 2008 at 4:05 AM, Laszlo Nagy <gandalf@shopzeus.com> wrote:
> We have serveral table where the index size is much bigger than the table
> size.
You'll usually get index bloat in roughly the same measure that you
get table bloat. If you always (auto)vacuum regularly, then the
amount of bloat in your indexes probably reflects the amount of bloat
that your tables typically accumulate between vacuums, so reindexing
won't help much. The indexes will just re-bloat back to about the
same point over the next vacuum cycle or two.
On the other hand, if your table has shrunk considerably, or if you've
just removed a lot of bloat by vacuuming, REINDEX is often warranted.
It would be nice if the system could automatically notice and correct
situations that currently require VACUUM FULL or REINDEX, but it
doesn't.
...Robert
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-performance@postgresql.org
Cc: robertmhaas@gmail.com, gandalf@shopzeus.com
Subject: Re: Big index sizes
In-Reply-To: <603c8f070812300643n3bcc0454j2022d4efaa6122d5@mail.gmail.com>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox