RFR: 8337217: Port VirtualMemoryTracker to use VMATree

[Johan Sjölen]

On Thu, 1 Aug 2024 15:44:32 GMT, Afshin Zafari <azafari at openjdk.org> wrote:

> - `VMATree` is used instead of `SortedLinkList` in new class `VirtualMemoryTrackerWithTree`.
>  -  A wrapper/helper `RegionTree` is made around VMATree to make some calls easier.
>  -  Both old and new versions exist in the code and can be selected via `MemTracker::set_version()`
>  - `find_reserved_region()` is used in 4 cases, it will be removed in further PRs.
>  - All tier1 tests pass except one ~that expects a 50% increase in committed memory but it does not happen~  https://bugs.openjdk.org/browse/JDK-8335167.
>  - Adding a runtime flag for selecting the old or new version can be added later.
>  - Some performance tests are added for new version, VMATree and Treap, to show the idea and should be improved later. Based on the results of comparing speed of VMATree and VMT, VMATree shows ~40x faster response time.

I was actually hoping that we could close this PR and open a new one when this moves out of draft, in order to have a clean slate for reviews to start from. This is fine, however.

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PR Comment: https://git.openjdk.org/jdk/pull/20425#issuecomment-2464656724