Jim C. Nasby wrote:
> The advantage to keying this to autovac_naptime is that it means we
> don't need another GUC, but after I suggested that before I realized
> that's probably not the best idea. For example, I've seen clusters that
> are running dozens-hundreds of databases; in that environment you really
> need to turn naptime way down (to like a second). In that case you
> wouldn't want to key to naptime.
Actually, I've been thinking that it would be a good idea to change the
semantics of autovacuum_naptime so that it means the average time to
start a worker in any given database. That way, the time between
autovac runs is not dependent on the number of databases you have.
--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.