diff --git a/src/runtime/malloc.go b/src/runtime/malloc.go
index b24ebec27d2..a35f806aa3e 100644
--- a/src/runtime/malloc.go
+++ b/src/runtime/malloc.go
@@ -227,7 +227,7 @@ const (
 	// --------------  ---------  ----------  ----------  -----------
 	//       */64-bit         48        64MB           1    4M (32MB)
 	// windows/64-bit         48         4MB          64    1M  (8MB)
-	//      ios/arm64         33         4MB           1  2048  (8KB)
+	//      ios/arm64         40         4MB           1  256K  (2MB)
 	//       */32-bit         32         4MB           1  1024  (4KB)
 	//     */mips(le)         31         4MB           1   512  (2KB)