From 99fa98766fa59270083606d9386386c3e7131a7a Mon Sep 17 00:00:00 2001 From: Alvaro Herrera Date: Wed, 8 Nov 2023 16:44:08 +0100 Subject: [PATCH] Call pqPipelineFlush from PQsendFlushRequest When PQsendFlushRequest() was added by commit 69cf1d5429d4, we argued against adding a PQflush() call in it[1]. This is still the right decision: if the user wants a flush to occur, they can just call that. However, we failed to realize that the message bytes could still be given to the kernel for transmitting when this can be made without blocking. That's what pqPipelineFlush() does, and it is done for every single other message type sent by libpq, so do that. (When the socket is in blocking mode this may indeed block, but that's what all the other libpq message-sending routines do, too.) [1] https://www.postgresql.org/message-id/202106252352.5ca4byasfun5%40alvherre.pgsql Author: Jelte Fennema-Nio Discussion: https://postgr.es/m/CAGECzQTxZRevRWkKodE-SnJk1Yfm4eKT+8E4Cyq3MJ9YKTnNew@mail.gmail.com --- src/interfaces/libpq/fe-exec.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/src/interfaces/libpq/fe-exec.c b/src/interfaces/libpq/fe-exec.c index 1800d7365be..08326895ee4 100644 --- a/src/interfaces/libpq/fe-exec.c +++ b/src/interfaces/libpq/fe-exec.c @@ -3252,6 +3252,14 @@ PQsendFlushRequest(PGconn *conn) return 0; } + /* + * Give the data a push (in pipeline mode, only if we're past the size + * threshold). In nonblock mode, don't complain if we're unable to send + * it all; PQgetResult() will do any additional flushing needed. + */ + if (pqPipelineFlush(conn) < 0) + return 0; + return 1; } -- 2.39.5