JDK-8368080 : G1: Unnecessary initialization of G1CMTask's mark stats table
  • Type: Enhancement
  • Component: hotspot
  • Sub-Component: gc
  • Priority: P4
  • Status: Open
  • Resolution: Unresolved
  • Submitted: 2025-09-19
  • Updated: 2025-09-22
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tbdUnresolved
Related Reports
Relates :  
JDK-8359802 - JEP 523: Make G1 the Default Garbage Collector in All Environments
Relates :  
JDK-8367993 - G1: Speed up ConcurrentMark initialization
Description
During initialization of the CMTask G1 resets the stats table, effectively pre-touching it.

This sometimes shows up in startup profiles, so maybe by not doing it at startup we avoid some pre-touching of that area, but at least avoid doing the work.

The tables will be reset during mark start anyways.

See also JDK-8367993
Comments
A pull request was submitted for review. Branch: master URL: https://git.openjdk.org/jdk/pull/27390 Date: 2025-09-19 11:49:59 +0000
22-09-2025