JDK-8371791 : G1: Improve accuracy of G1CollectedHeap::non_young_occupancy_after_allocation()
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: gc
  • Priority: P4
  • Status: Resolved
  • Resolution: Fixed
  • Submitted: 2025-11-13
  • Updated: 2025-11-24
  • Resolved: 2025-11-14
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JDK 26
26 b25Fixed
Related Reports
Relates :  
JDK-8274178 - G1: Occupancy value in IHOP logging and JFR event is inaccurate
Description
Currently G1CollectedHeap::non_young_occupancy_after_allocation() bases non-young occupancy on regions. All old gen regions are always completely full. This disregards the free space at the end of the old retained region where we can still allocate into.

By taking this free space into account, we can delay concurrent mark a little.
Comments
Changeset: 4cc655a2 Branch: master Author: Thomas Schatzl <tschatzl@openjdk.org> Date: 2025-11-14 12:49:46 +0000 URL: https://git.openjdk.org/jdk/commit/4cc655a2f445bb32ce555b80ac28610b26c51f4c
14-11-2025
A pull request was submitted for review. Branch: master URL: https://git.openjdk.org/jdk/pull/28294 Date: 2025-11-13 14:00:47 +0000
13-11-2025