diff --git a/src/backend/replication/slot.c b/src/backend/replication/slot.c
index 505445f2dc..72aa5de60c 100644
--- a/src/backend/replication/slot.c
+++ b/src/backend/replication/slot.c
@@ -99,6 +99,8 @@ ReplicationSlot *MyReplicationSlot = NULL;
 int			max_replication_slots = 0;	/* the maximum number of replication
 										 * slots */
 
+static int ReplicationSlotAcquireInternal(const char *name,
+										  SlotAcquireBehavior behavior, int index);
 static void ReplicationSlotDropAcquired(void);
 static void ReplicationSlotDropPtr(ReplicationSlot *slot);
 
@@ -332,25 +334,45 @@ ReplicationSlotCreate(const char *name, bool db_specific,
  */
 int
 ReplicationSlotAcquire(const char *name, SlotAcquireBehavior behavior)
+{
+	int			i;
+
+	/*
+	 * Search for the named slot and mark it active if we find it.
+	 */
+	LWLockAcquire(ReplicationSlotControlLock, LW_SHARED);
+	for (i = 0; i < max_replication_slots; i++)
+	{
+		ReplicationSlot *s = &ReplicationSlotCtl->replication_slots[i];
+
+		if (s->in_use && strcmp(name, NameStr(s->data.name)) == 0)
+			break;
+	}
+	LWLockRelease(ReplicationSlotControlLock);
+
+	return ReplicationSlotAcquireInternal(name, behavior, i);
+}
+
+static int
+ReplicationSlotAcquireInternal(const char *name,
+							   SlotAcquireBehavior behavior, int index)
 {
 	ReplicationSlot *slot;
 	int			active_pid;
-	int			i;
 
 retry:
 	Assert(MyReplicationSlot == NULL);
 
 	/*
-	 * Search for the named slot and mark it active if we find it.  If the
-	 * slot is already active, we exit the loop with active_pid set to the PID
+	 * If the slot is already active, we set active_pid to the PID
 	 * of the backend that owns it.
 	 */
 	active_pid = 0;
 	slot = NULL;
 	LWLockAcquire(ReplicationSlotControlLock, LW_SHARED);
-	for (i = 0; i < max_replication_slots; i++)
+	if (index >= 0 && index < max_replication_slots)
 	{
-		ReplicationSlot *s = &ReplicationSlotCtl->replication_slots[i];
+		ReplicationSlot *s = &ReplicationSlotCtl->replication_slots[index];
 
 		if (s->in_use && strcmp(name, NameStr(s->data.name)) == 0)
 		{
@@ -378,8 +400,6 @@ retry:
 			else
 				active_pid = MyProcPid;
 			slot = s;
-
-			break;
 		}
 	}
 	LWLockRelease(ReplicationSlotControlLock);
@@ -1120,8 +1140,9 @@ restart:
 
 		for (;;)
 		{
-			int			wspid = ReplicationSlotAcquire(NameStr(slotname),
-													   SAB_Inquire);
+			int			wspid =
+				ReplicationSlotAcquireInternal(NameStr(slotname),
+											   SAB_Inquire, i);
 
 			/* no walsender? success! */
 			if (wspid == 0)