Shridhar,
I was looking at the -V/-v and -A/-a settings in pgavd, and really don't
understand how the calculation works. According to the readme, if I set -v
to 1000 and -V to 2 (the defaults) for a table with 10,000 rows, pgavd would
only vacuum after 21,000 rows had been updated. This seems wrong.
Can you clear this up a little? I'd like to tweak these settings but can't
without being better aquainted with the calculation.
Also, you may want to reverse your default ratio for Vacuum/analyze frequency.
True, analyze is a less expensive operation than Vacuum, but it's also needed
less often -- only when the *distribution* of data changes. I've seen
databases where the optimal vacuum/analyze frequency was every 10 min/once
per day.
--
-Josh Berkus
Aglio Database Solutions
San Francisco
