On Thu, Aug 13, 2009 at 5:15 PM, Josh Berkus<josh@xxxxxxxxxxxx> wrote: > Robert, > >> Ah. Yeah, I agree with Tom: how would it help to make this smaller? >> It seems like that could possibly increase I/O, if the old data is >> changing at all, but even if it doesn't it I don't see that it saves >> you anything to freeze it sooner. > > Before 8.4, it actually does on tables which are purely cumulative > (WORM). Within a short time, say, 10,000 transactions, the rows to be > frozen are still in the cache. By 100m transactions, they are in an > archive partition which will need to be dragged from disk. So if I know > they won't be altered, then freezing them sooner would be better. > > However, I can easily manage this through the autovacuum settings. I > just wanted confirmation of what I was thinking. Interesting. Thanks for the explanation. ...Robert -- Sent via pgsql-performance mailing list (pgsql-performance@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance
