Обсуждение: Disk usage in postgresql 8.1.4

On Sun, Aug 06, 2006 at 04:42:47PM -0700, Geoff Parker wrote:
>  I've got a database with about 155GB of binary data, however
> when I run the unix utility df, it reports only 60GB of disk space
> is being used.   I've extracted random samples of data from the
> database, and it all appears correct, so I presume it's not corrupt.
> Can anyone tell me whether there's some sort of disk compression
> happening with large objects?

Large objects are stored in pg_largeobject as chunks of bytea data,
which can be compressed.

--
Michael Fuhr

On Aug 6, 2006, at 6:42 PM, Geoff Parker wrote:
> Hi,
> I've got a database with about 155GB of binary data, however when I
> run the unix utility df, it reports only 60GB of disk space is
> being used.   I've extracted random samples of data from the
> database, and it all appears correct, so I presume it's not
> corrupt.   Can anyone tell me whether there's some sort of disk
> compression happening with large objects?
>
> Has anyone else seen this behaviour?
>
> # df
> Filesystem           1K-blocks      Used Available Use% Mounted on
> /dev/mapper/VolGroup01-ATV_PGSQL
>                      480678616  59285468 396976076  13% /var/lib/pgsql
>
> This is Postresql version 8.1.4 on a slightly modified version of
> RHEL 4 (2.6.17 kernel).

You sure you're not using tablespaces?
--
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