Jesper Krogh <jesper@xxxxxxxx> wrote: > My thought was that if I tuned autovacuum to be "really > aggressive" then I could get autovacuum to actually vacuum the > tuples before they get evicted from the OS cache thus effectively > "saving" the IO-overhead of vacuuming. Interesting concept. That might be a way to avoid the extra disk I/O to set hint bits, and then some. I haven't tried it, but I'm going to make a note to take a look when (if???) I get some free time. If you give it a try, please post the results. If you're I/O bound (rather than CPU bound) and you choose *extremely* aggressive settings, the multiple writes to pages *might* collapse in cache and significantly reduce I/O. I don't think I'd try it on a release prior to 8.4, however. Nor would I consider trying this in a production environment without a good set of tests. -Kevin -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
