Re: performance; disk bad or something?

On Sat, Apr 07, 2007 at 09:28:58AM +0200, Marcus Engene wrote:
> INFO: "apa_item_common": removed 9028 row versions in 3651 pages
> DETAIL: CPU 0.24s/0.36u sec elapsed 30.69 sec.
> INFO: "apa_item_common": found 9028 removable, 12863 nonremovable row
> versions in 14489 pages
> DETAIL: 0 dead row versions cannot be removed yet.
> There were 76646 unused item pointers.

How often does this table receive updates and deletes and how often
are you vacuuming it? It averages less than one row per page (12863
nonremovable row versions in 14489 pages) and appears to have become
quite bloated with dead rows sometime in the past (76646 unused
item pointers). Use CLUSTER or VACUUM FULL + REINDEX to compact
the table and run ANALYZE afterwards to update the statistics, then
make sure you're vacuuming it often enough to keep it from becoming
bloated again.

Is your free space map sufficiently sized? If you do a database-wide
VACUUM VERBOSE, what are the last few lines of the output that
mention free space map settings?

--
Michael Fuhr