From d6ca510d9dbacceb3444f00fcfbba2c80dca4c8f Mon Sep 17 00:00:00 2001 From: Joe Conway Date: Sat, 7 Dec 2013 17:00:26 -0800 Subject: [PATCH] Fix performance regression in dblink connection speed. Previous commit e5de601267d98c5d60df6de8d436685c7105d149 modified dblink to ensure client encoding matched the server. However the added PQsetClientEncoding() call added significant overhead. Restore original performance in the common case where client encoding already matches server encoding by doing nothing in that case. Applies to all active branches. Issue reported and work sponsored by Zonar Systems. --- contrib/dblink/dblink.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/contrib/dblink/dblink.c b/contrib/dblink/dblink.c index 093324de99..a91a547ada 100644 --- a/contrib/dblink/dblink.c +++ b/contrib/dblink/dblink.c @@ -209,7 +209,8 @@ typedef struct remoteConnHashEnt errdetail_internal("%s", msg))); \ } \ dblink_security_check(conn, rconn); \ - PQsetClientEncoding(conn, GetDatabaseEncodingName()); \ + if (PQclientEncoding(conn) != GetDatabaseEncoding()) \ + PQsetClientEncoding(conn, GetDatabaseEncodingName()); \ freeconn = true; \ } \ } while (0) @@ -288,8 +289,9 @@ dblink_connect(PG_FUNCTION_ARGS) /* check password actually used if not superuser */ dblink_security_check(conn, rconn); - /* attempt to set client encoding to match server encoding */ - PQsetClientEncoding(conn, GetDatabaseEncodingName()); + /* attempt to set client encoding to match server encoding, if needed */ + if (PQclientEncoding(conn) != GetDatabaseEncoding()) + PQsetClientEncoding(conn, GetDatabaseEncodingName()); if (connname) {