Re: Postgresql 'eats' all mi data partition

On Thu, 25 Sep 2003, Javier Carlos wrote:

> ============================================================================
> POSTGRESQL BUG REPORT TEMPLATE
> ============================================================================
>
>
> Your name : Javier Carlos Rivera
> Your email address : fjcarlos ( at ) correo ( dot ) insp ( dot ) mx
>
>
> System Configuration
> ----------------------
> Architecture (example: Intel Pentium) : Intel Pentium 4
>
> Operating System (example: Linux 2.0.26 ELF) : Debian GNU/Linux 3.0 2.4.21
>
> RAM : 256 MB
>
> PostgreSQL version (example: PostgreSQL-6.3.2) : PostgreSQL-7.3.4
>
> Compiler used (example: gcc 2.7.2) : 2.95.4
>
>
>
> Please enter a FULL description of your problem:
> -------------------------------------------------
> On Thursday Bruce Momjian was at Mexico; I saw him and asked about
> this problem. He told me to write to this e-mail.
>
> When I do a simple 'UPDATE' PostgreSQL 'eats' all my partition space
> of my data directory. For example:
>
> ***** My data directory is in /var
> ***** BEFORE I do the UPDATEs I got this from df:
> OPORTUNIDADES:~# df
> Filesystem 1k-blocks Used Available Use% Mounted on
> /dev/hda2 2885812 14372 2724848 1% /
> /dev/hda1 14421344 1195132 12493652 9% /var
> /dev/hda3 7692908 888560 6413568 13% /usr
> /dev/hda6 12491804 22704 11834536 1% /javier
> /dev/hda7 1494204 23936 1394364 2% /home
>
>
> ***** Then I do the UPDATEs:
> **** The updates are of this type :
> UPDATE tbl_personas SET "PIDFOLIO"=-2 WHERE "PIDFOLIO" IS NULL;
> UPDATE tbl_personas SET "P5_1"=-2 WHERE "P5_1" IS NULL;
> UPDATE tbl_personas SET "P4PAQ"=-2 WHERE "P4PAQ" IS NULL;
> UPDATE tbl_personas SET "P5_4"=-2 WHERE "P5_4" IS NULL;
> UPDATE tbl_personas SET "P5_5"=-2 WHERE "P5_5" IS NULL;
> UPDATE tbl_personas SET "P36_4"=-2 WHERE "P36_4" IS NULL;
> ..
> UPDATE table_name SET column_name = -2 WHERE column_name IS NULL;
> ..

If you're not vacuuming, you're going to have a potentially large
number of dead rows. Does a vacuum between updates or a vacuum full at
the end bring the space usage down to something reasonable?