On Thu, Sep 22, 2016 at 3:51 PM, Heikki Linnakangas <hlinn...@iki.fi> wrote: > It'd be good if you could overlap the final merges in the workers with the > merge in the leader. ISTM it would be quite straightforward to replace the > final tape of each worker with a shared memory queue, so that the leader > could start merging and returning tuples as soon as it gets the first tuple > from each worker. Instead of having to wait for all the workers to complete > first.
If you do that, make sure to have the leader read multiple tuples at a time from each worker whenever possible. It makes a huge difference to performance. See bc7fcab5e36b9597857fa7e3fa6d9ba54aaea167. -- Robert Haas EnterpriseDB: http://www.enterprisedb.com The Enterprise PostgreSQL Company -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
