From 9b8aa0929390aab1f2f0859016e6110d283732dd Mon Sep 17 00:00:00 2001 From: Thomas Munro Date: Wed, 18 Mar 2020 12:48:13 +1300 Subject: [PATCH] Don't use EV_CLEAR for kqueue events. For the semantics to match the epoll implementation, we need a socket to continue to appear readable/writable if you wait multiple times without doing I/O in between (in Linux terminology: level-triggered rather than edge-triggered). This distinction will be important for later commits. Similar to commit 3b790d256f8 for Windows. Reviewed-by: Kyotaro Horiguchi Discussion: https://postgr.es/m/CA%2BhUKGJAC4Oqao%3DqforhNey20J8CiG2R%3DoBPqvfR0vOJrFysGw%40mail.gmail.com --- src/backend/storage/ipc/latch.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/src/backend/storage/ipc/latch.c b/src/backend/storage/ipc/latch.c index d4c6c65baa..e2f4b116b9 100644 --- a/src/backend/storage/ipc/latch.c +++ b/src/backend/storage/ipc/latch.c @@ -991,7 +991,7 @@ WaitEventAdjustKqueueAdd(struct kevent *k_ev, int filter, int action, { k_ev->ident = event->fd; k_ev->filter = filter; - k_ev->flags = action | EV_CLEAR; + k_ev->flags = action; k_ev->fflags = 0; k_ev->data = 0; AccessWaitEvent(k_ev) = event; @@ -1003,7 +1003,7 @@ WaitEventAdjustKqueueAddPostmaster(struct kevent *k_ev, WaitEvent *event) /* For now postmaster death can only be added, not removed. */ k_ev->ident = PostmasterPid; k_ev->filter = EVFILT_PROC; - k_ev->flags = EV_ADD | EV_CLEAR; + k_ev->flags = EV_ADD; k_ev->fflags = NOTE_EXIT; k_ev->data = 0; AccessWaitEvent(k_ev) = event; -- 2.39.5