Yudhvir Singh Sidhu wrote:
Versions: Postgresql version 8.09 on FreeBSD 6.1
Situation: huge amounts of adds and deletes daily. Running daily vacuums
Problem: Vacuum times jump up from 45 minutes, or 1:30 minutes to 6+
hours overnight, once every 1 to 3 months.
Solutions tried: db truncate - brings vacuum times down. Reindexing
brings vacuum times down.
I know my indexes are getting fragmented and my tables are getting
fragmented. I also know that some of my btree indexes are not being used
in queries. I also know that using "UNIQUE" in a query makes PG ignore
any index.
If the increase in vacuum time is indeed because of index fragmentation,
upgrading to 8.2 might help. Since 8.2, we vacuum indexes in physical
order, which speeds it up significantly, especially on fragmented indexes.
--
Heikki Linnakangas
EnterpriseDB http://www.enterprisedb.com
