diff --git a/src/test/modules/xid_wraparound/xid_wraparound.c b/src/test/modules/xid_wraparound/xid_wraparound.c
index dce81c0c6d..70a748c41d 100644
--- a/src/test/modules/xid_wraparound/xid_wraparound.c
+++ b/src/test/modules/xid_wraparound/xid_wraparound.c
@@ -34,11 +34,8 @@ consume_xids(PG_FUNCTION_ARGS)
 	int64		nxids = PG_GETARG_INT64(0);
 	FullTransactionId lastxid;
 
-	if (nxids < 0)
+	if (nxids <= 0)
 		elog(ERROR, "invalid nxids argument: %lld", (long long) nxids);
-
-	if (nxids == 0)
-		lastxid = ReadNextFullTransactionId();
 	else
 		lastxid = consume_xids_common(InvalidFullTransactionId, (uint64) nxids);
 
@@ -89,7 +86,11 @@ consume_xids_common(FullTransactionId untilxid, uint64 nxids)
 	 * the cache overflows, but beyond that, we don't keep track of the
 	 * consumed XIDs.
 	 */
-	(void) GetTopTransactionId();
+	if(!FullTransactionIdIsValid(GetTopFullTransactionIdIfAny()))
+	{
+		lastxid = GetTopTransactionId();
+		consumed++;
+	}
 
 	for (;;)
 	{