Bruce Momjian wrote: > I think the limit has to be in terms of a percentage of the table size. > For example, if we do one SELECT on a table with all non-dirty pages, it > would be good to know that 5% of the pages were pruned --- that tells me > that another 19 SELECTs will totally prune the table, assuming no future > writes.
This seems simple to implement: keep two counters, where the second one is pages we skipped cleanup in. Once that counter hits SOME_MAX_VALUE, reset the first counter so that further 5 pages will get HOT pruned. 5% seems a bit high though. (In Simon's design, SOME_MAX_VALUE is essentially +infinity.) -- Álvaro Herrera http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
