RFR: 8316813: NMT: Using WhiteBox API, virtual memory tracking should also be stressed in JMH tests [v2]

[Gerard Ziemski]

On Mon, 12 Feb 2024 13:50:37 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

> I wonder, though, how much value this benchmark really has. Since we now measure both the mmap call and the registration with NMT. The mmap call may dominate, and/or bring a lot of randomness, since it depends on the context (e.g. do we swap, do we have pages in cache etc).

I think the more data we have the better. Once we start getting more comfortable in this area (we are still learning) we will surely know how to read and use the results, but for now, I personally think that we should be gathering the data anywhere we can, to look for patterns and to learn from them. I'm curious to see, for example, if the randomness you are predicting will show up, and if so, how strong ...

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PR Comment: https://git.openjdk.org/jdk/pull/17582#issuecomment-1939289909