From 16da81eb439e48459e4ca19d6f97c0de5e2d2398 Mon Sep 17 00:00:00 2001
From: Matthias Baesken <mbaesken@openjdk.org>
Date: Wed, 30 Jul 2025 12:28:14 +0000
Subject: [PATCH] 8360817: [ubsan] zDirector select_worker_threads - outside
 the range of representable values issue

Reviewed-by: aboldtch, lucy
---
 src/hotspot/share/gc/z/zDirector.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/hotspot/share/gc/z/zDirector.cpp b/src/hotspot/share/gc/z/zDirector.cpp
index f1256eecd19..e46b1c9e167 100644
--- a/src/hotspot/share/gc/z/zDirector.cpp
+++ b/src/hotspot/share/gc/z/zDirector.cpp
@@ -556,7 +556,7 @@ static double calculate_young_to_old_worker_ratio(const ZDirectorStats& stats) {
 
   const double old_vs_young_efficiency_ratio = current_old_bytes_freed_per_gc_time / current_young_bytes_freed_per_gc_time;
 
-  return old_vs_young_efficiency_ratio;
+  return MIN2(old_vs_young_efficiency_ratio, (double)ZOldGCThreads);
 }
 
 static bool rule_major_proactive(const ZDirectorStats& stats) {