Summary

The option -XX:+/-UseCompactObjectHeaders is now a product option, and no longer experimental.

Problem

The compact object headers feature (JEP 450) reduces memory footprint and potentially improves performance of Java applications. The option should be available to all users without requiring -XX:+UnlockExperimentalVMOptions. Going forward, the option should become enabled by default in a future release.

Solution

Remove experimantal status of the flag UseCompactObjectHeaders.

Specification

diff --git a/src/hotspot/share/runtime/globals.hpp b/src/hotspot/share/runtime/globals.hpp
index ab975b1b375c0..90b31f841507c 100644
--- a/src/hotspot/share/runtime/globals.hpp
+++ b/src/hotspot/share/runtime/globals.hpp
@@ -128,7 +128,7 @@ const size_t minimumSymbolTableSize = 1024;
           "Use 32-bit class pointers in 64-bit VM. "                        \
           "lp64_product means flag is always constant in 32 bit VM")        \
                                                                             \
-  product(bool, UseCompactObjectHeaders, false, EXPERIMENTAL,               \
+  product(bool, UseCompactObjectHeaders, false,                             \
           "Use compact 64-bit object headers in 64-bit VM")                 \
                                                                             \
   product(int, ObjectAlignmentInBytes, 8,                                   \