6 files changed, 15 insertions, 3 deletions
diff --git a/src/backend/commands/subscriptioncmds.c b/src/backend/commands/subscriptioncmds.c
index 005e74201d4..77620dfd429 100644
--- a/src/backend/commands/subscriptioncmds.c
+++ b/src/backend/commands/subscriptioncmds.c
@@ -959,7 +959,7 @@ DropSubscription(DropSubscriptionStmt *stmt, bool isTopLevel)
 	load_file("libpqwalreceiver", false);
 
 	initStringInfo(&cmd);
-	appendStringInfo(&cmd, "DROP_REPLICATION_SLOT %s", quote_identifier(slotname));
+	appendStringInfo(&cmd, "DROP_REPLICATION_SLOT %s WAIT", quote_identifier(slotname));
 
 	wrconn = walrcv_connect(conninfo, true, subname, &err);
 	if (wrconn == NULL)
diff --git a/src/backend/replication/repl_gram.y b/src/backend/replication/repl_gram.y
index ec047c827cf..a012447fa2a 100644
--- a/src/backend/replication/repl_gram.y
+++ b/src/backend/replication/repl_gram.y
@@ -72,6 +72,7 @@ static SQLCmd *make_sqlcmd(void);
 %token K_LABEL
 %token K_PROGRESS
 %token K_FAST
+%token K_WAIT
 %token K_NOWAIT
 %token K_MAX_RATE
 %token K_WAL
@@ -272,6 +273,15 @@ drop_replication_slot:
 					DropReplicationSlotCmd *cmd;
 					cmd = makeNode(DropReplicationSlotCmd);
 					cmd->slotname = $2;
+					cmd->wait = false;
+					$$ = (Node *) cmd;
+				}
+			| K_DROP_REPLICATION_SLOT IDENT K_WAIT
+				{
+					DropReplicationSlotCmd *cmd;
+					cmd = makeNode(DropReplicationSlotCmd);
+					cmd->slotname = $2;
+					cmd->wait = true;
 					$$ = (Node *) cmd;
 				}
 			;
diff --git a/src/backend/replication/repl_scanner.l b/src/backend/replication/repl_scanner.l
index 52ae7b343fb..62bb5288c01 100644
--- a/src/backend/replication/repl_scanner.l
+++ b/src/backend/replication/repl_scanner.l
@@ -103,6 +103,7 @@ TEMPORARY			{ return K_TEMPORARY; }
 EXPORT_SNAPSHOT		{ return K_EXPORT_SNAPSHOT; }
 NOEXPORT_SNAPSHOT	{ return K_NOEXPORT_SNAPSHOT; }
 USE_SNAPSHOT		{ return K_USE_SNAPSHOT; }
+WAIT				{ return K_WAIT; }
 
 ","				{ return ','; }
 ";"				{ return ';'; }
diff --git a/src/backend/replication/slotfuncs.c b/src/backend/replication/slotfuncs.c
index d4cbd83bde1..ab776e85d2f 100644
--- a/src/backend/replication/slotfuncs.c
+++ b/src/backend/replication/slotfuncs.c
@@ -171,7 +171,7 @@ pg_drop_replication_slot(PG_FUNCTION_ARGS)
 
 	CheckSlotRequirements();
 
-	ReplicationSlotDrop(NameStr(*name), false);
+	ReplicationSlotDrop(NameStr(*name), true);
 
 	PG_RETURN_VOID();
 }
diff --git a/src/backend/replication/walsender.c b/src/backend/replication/walsender.c
index 03e1cf44dee..db346e6edbd 100644
--- a/src/backend/replication/walsender.c
+++ b/src/backend/replication/walsender.c
@@ -1028,7 +1028,7 @@ CreateReplicationSlot(CreateReplicationSlotCmd *cmd)
 static void
 DropReplicationSlot(DropReplicationSlotCmd *cmd)
 {
-	ReplicationSlotDrop(cmd->slotname, false);
+	ReplicationSlotDrop(cmd->slotname, !cmd->wait);
 	EndCommand("DROP_REPLICATION_SLOT", DestRemote);
 }
 
diff --git a/src/include/nodes/replnodes.h b/src/include/nodes/replnodes.h
index dea61e90e96..2053ffabe09 100644
--- a/src/include/nodes/replnodes.h
+++ b/src/include/nodes/replnodes.h
@@ -68,6 +68,7 @@ typedef struct DropReplicationSlotCmd
 {
 	NodeTag		type;
 	char	   *slotname;
+	bool		wait;
 } DropReplicationSlotCmd;