On Fri, Oct 21, 2011 at 12:52 PM, Robert Haas <robertmh...@gmail.com> wrote: > > Also, this line is kind of expensive: > > if (!visibilitymap_test(scandesc->heapRelation, > ItemPointerGetBlockNumber(tid), > &node->ioss_VMBuffer)) > > Around 2%. But I don't see any way to avoid that, or even make it cheaper.
Could we cache by ItemPointerGetBlockNumber(tid) the results of those tests, for groups of tids on the same index page? How useful this would be would depend on how well-clustered the table and index are. Cheers, Jeff -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers