RFR: 8360048: NMT crash in gtest/NMTGtests.java: fatal error: NMT corruption: Block at 0x0000017748307120: header canary broken [v2]

[Gerard Ziemski]

On Tue, 24 Jun 2025 13:27:15 GMT, Johan Sjölen <jsjolen at openjdk.org> wrote:

>> test/hotspot/gtest/runtime/test_virtualMemoryTracker.cpp line 452:
>> 
>>> 450:       MemTracker::NmtVirtualMemoryLocker nvml;
>>> 451:       rtree = VirtualMemoryTracker::Instance::tree();
>>> 452:       rtree->tree().remove_all();
>> 
>> I think I asked about this before - can we  do remove_all  in the constructor to avoid this 2 line repeating pattern?
>> 
>> Otherwise looks good, can you please check the GHA test failures on Windows?
>
> I don't think that's the right way to go. I think it's better if we can avoid using the global instance, and not change the code of the VMT in order to appease the tests.

Sure, I suggested the easiest fix I could think of, but doing it this way is even better!

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PR Review Comment: https://git.openjdk.org/jdk/pull/25950#discussion_r2164469900