JDK-8370682 : G1: Survivor regions not in young gen cset group
  • Type: Bug
  • Component: hotspot
  • Sub-Component: gc
  • Affected Version: 24
  • Priority: P4
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2025-10-27
  • Updated: 2025-11-11
  • Resolved: 2025-11-04
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JDK 26
26 b23Fixed
Related Reports
Causes :  
JDK-8336086 - G1: Use one G1CardSet instance for all young regions
Description
Currently, after GC the survivor regions are not part of young gen cset group because we clear them from there when preparing for the next mutator phase.

I.e. the young gen cset group does not contain a reference to them, but the regions themselves still have it.

Apart from an issue during full gc where we need to uninstall their cset group references manually (instead of being handled while abandoning the young gen cset group) I do not think there is an issue.

The suspicious code has been introduced by JDK-8343782, but I think JDK-8336086 already had that issue but it was less explicit.
Comments
Changeset: e4aed95c Branch: master Author: Thomas Schatzl <tschatzl@openjdk.org> Date: 2025-11-04 08:48:48 +0000 URL: https://git.openjdk.org/jdk/commit/e4aed95cac343f1339b9bc87721561bdc4c2f5ad
04-11-2025
A pull request was submitted for review. Branch: master URL: https://git.openjdk.org/jdk/pull/28056 Date: 2025-10-30 09:55:11 +0000
30-10-2025