Re: VACUUM FULL ANALYZE on 8.1.4 is slower then on 8.0

On Thu, Oct 19, 2006 at 03:30:35PM +0200, Andrzej Zawadzki wrote:
> After upgrade PostgreSQL from 8.0 to 8.1.4 a VACUUM FULL ANALYZE
> process is much slower, from logs:

Are you sure you need VACUUM FULL?  If you're vacuuming often enough
and your free space map settings are adequate then plain VACUUM
(without FULL) should suffice for routine use.

> 8.0
> [13666][postgres][2006-10-06 01:13:38 CEST][1340121452] LOG:  statement: VACUUM FULL ANALYZE;
> [13666][postgres][2006-10-06 01:39:15 CEST][0] LOG:  duration: 1536862.425 ms
>
>
> 8.1
> [4535][postgres][2006-10-10 01:08:51 CEST][6144112] LOG:  statement: VACUUM FULL ANALYZE;
> [4535][postgres][2006-10-10 02:04:23 CEST][0] LOG:  duration: 3332128.332 ms
>
> Databases are equal.

Equal how?  Number of tables?  Number of tuples?  Disk space used?
Activity, especially updates and deletes?  All of the above?

Have you used VACUUM VERBOSE to see how much work each VACUUM is doing?

Is it possible that 8.1 was built with --enable-cassert and 8.0
wasn't?  What does "SHOW debug_assertions" show on each server?

--
Michael Fuhr