RFR: 8335167: Test runtime/Thread/TestAlwaysPreTouchStacks.java failed with Expected a higher ratio between stack committed and reserved [v5]

[Afshin Zafari]

On Mon, 23 Sep 2024 08:55:12 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

>> If we don't save the Reserved and just look at it for each run independently, we get back to the original test which has problems in macos-aarch64 environments. We decided/agreed to have two tests and save the amounts and then compare them to check if pretouch was done or not.
>> Maybe I misunderstood you.
>
> @afshin-zafari I just mean that since you compare the committed values of two runs, one with and one without pretouch, you don't really need to compare the reserved values or calculate the reserved to committed ratio. In fact, in both cases, reserved should be near identical. 
> 
> All you really need to do is to make sure that committed (with pretouch) is > (committed (without pretouch) + expected delta). So, committed with pretouch should be at least 80MB larger than committed without pretouch.
> 
> Am I making a thinking error here?

Sorry for confusion. It is clear to me now. The changes are pushed.

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PR Review Comment: https://git.openjdk.org/jdk/pull/20531#discussion_r1771116734