On Tue, Dec 13, 2016 at 9:49 PM, Andres Freund <and...@anarazel.de> wrote: > On 2016-12-12 16:46:38 +0900, Michael Paquier wrote: >> OK, I think that I have spotted an issue after additional read of the >> code. When a WSA event is used for read/write activity on a socket, >> the same WSA event gets reused again and again. That's fine for >> performance reasons > > It's actually also required to not loose events, > i.e. correctness. Windows events are edge, not level triggered. >
Are all Windows events edge triggered? What I read from msdn [1], it doesn't appear so. I am quoting text from msdn page [1] which seems to be saying the event FD_READ we use in this case is level triggered. "For FD_READ, FD_OOB, and FD_ACCEPT network events, network event recording and event object signaling are level-triggered." > The > previous implementation wasn't correct. So just resetting things ain't > ok. > Okay, but I think we need to re-enable the existing event handle for required event (FD_READ) by using WSAEventSelect() to make it work sanely. We have tried something on those lines and it resolved the problem. Ashutosh will post a patch on those lines later today. Let us know if you have something else in mind. [1] - https://msdn.microsoft.com/en-us/library/windows/desktop/ms741576(v=vs.85).aspx -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
