Robert Haas <robertmh...@gmail.com> writes: > The delay code is stupider than it could be, in that it sleeps without > regard to what's happening elsewhere in the system. The futex stuff > was interesting to me because it potentially provides a way to sleep > "until something interesting happens" rather than "for a fixed amount > of time". But it's unclear to me what exactly we'd have to do to > squeeze out a win, or even whether it's possible.
Right. AFAICS, sleeping "until something happens" necessarily requires adding overhead on the other side, ie, lock releasers will have to do something extra to wake up sleepers. If that means adding overhead to low-contention cases, we could come out behind even if it improves high-contention cases. Tradeoffs, always tradeoffs ... regards, tom lane -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers