Fixed benchmark code.
diff --git a/reader_test.go b/reader_test.go
index e77ccb9..6c39d84 100644
--- a/reader_test.go
+++ b/reader_test.go
@@ -14,8 +14,8 @@
 	b.ResetTimer()
 
 	for i := int64(0); i < iterations; i++ {
-		lower, upper := reader.Receive()
-		reader.Commit(lower, upper)
+		_, upper := reader.Receive()
+		reader.Commit(upper)
 		read.Store(0)
 	}
 }