JDK-8366564 : Release Note: -XX:+UseTransparentHugePages fails to turn on huge pages for G1
  • Type: Sub-task
  • Component: hotspot
  • Sub-Component: gc
  • Affected Version: 25
  • Priority: P4
  • Status: New
  • Resolution: Unresolved
  • Submitted: 2025-09-01
  • Updated: 2025-09-02
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JDK 25
25Unresolved
Description
On systems configured with the Transparent Huge Pages (THP) mode as ´madvise´ the option `-XX:+UseTransparentHugePages` does not enable huge pages when running with the default garbage collector G1. 

A workaround to allow the use of transparent huge pages with G1 is to configure the THP mode as `always`:
```
# echo always > /sys/kernel/mm/transparent_hugepage/enabled
```

This issue will be fixed in a future update.
Comments
Reviewed by: stefank
02-09-2025