Kenji Morishige <kenjim@juniper.net> writes:
> Various users run a tool that updates this table to determine if the particular
> resource is available or not. Within a course of a few days, this table can
> be updated up to 200,000 times. There are only about 3500 records in this
> table, but the update and select queries against this table start to slow
> down considerablly after a few days. Ideally, this table doesn't even need
> to be stored and written to the filesystem. After I run a vacuum against this
> table, the overall database performance seems to rise again.
You should never have let such a table go that long without vacuuming.
You might consider using autovac to take care of it for you. If you
don't want to use autovac, set up a cron job that will vacuum the table
at least once per every few thousand updates.
regards, tom lane