On Jun 26, 2007, at 3:31 PM, Bill Moran wrote:
VACUUM FULL and REINDEX are not required to maintain disk usage. Good old- fashoned VACUUM will do this as long as your FSM settings are high enough.
I find this true for the data but not necessarily for indexes. The other week I reindexed a couple of O(100,000,000) row tables and shaved about 20Gb of index bloat. Those tables are vacuumed regularly, but we do a large data purge every few weeks. I think that causes some issues. I'm running 8.1.
To mitigate the downtime, we make use of the fact that we have live replica of the database on similarly capable hardware so we bring the replica offline, reindex it, bring it back up, move the "master" to it, then reindex the other server, and move the master back.