RFR: 8357445: G1: Time-Based Heap Uncommit During Idle Periods [v4]

[Thomas Schatzl]

On Thu, 17 Jul 2025 12:37:11 GMT, Ivan Walulya <iwalulya at openjdk.org> wrote:

>> Monica Beckwith has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   8357445: Remove redundant record_activity calls and leftover initialize call
>>   
>>   - Remove record_activity() from retirement methods as hr_clear() is always last
>>   - Remove leftover initialize() call since initialization moved to constructor
>>   - Remove unused G1 includes from vmOperations after moving VM_G1ShrinkHeap
>
> src/hotspot/share/gc/g1/g1HeapEvaluationTask.hpp line 36:
> 
>> 34: // Time-based heap evaluation task that runs during idle periods.
>> 35: // Uses PeriodicTask rather than G1ServiceTask due to build compatibility issues
>> 36: // in JDK 25+. PeriodicTask's 10ms granularity is adequate for heap evaluation
> 
> Can you please elaborate on these "compatibility issues"

+1. I would absolutely try to avoid subscribing to `PeriodicTask`. Is there something missing with `G1ServiceTask`?

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/26240#discussion_r2303638363