RFR: 8263236: runtime/os/TestTracePageSizes.java fails on old kernels [v3]

[Aleksey Shipilev]

On Thu, 6 May 2021 09:49:37 GMT, Aleksey Shipilev <shade at openjdk.org> wrote:

>> See the bug report for details. On some kernels, the madvise hint is not reflected in `/proc/smaps`. Instead, we can use a secondary evidence and read `AnonHugePages`.
>> 
>> Additional testing:
>>  - [x] Test with kernel 5.4.0 (still passes)
>>  - [x] Test with kernel 4.9.0 (used to fail, now passes)
>
> Aleksey Shipilev has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains five additional commits since the last revision:
> 
>  - Merge branch 'master' into JDK-8263236-trace-page-sizes
>  - Merge branch 'master' into JDK-8263236-trace-page-sizes
>  - Merge branch 'master' into JDK-8263236-trace-page-sizes
>  - Make jcheck happy: remove the TAB
>  - 8263236: runtime/os/TestTracePageSizes.java fails on old kernels

Ran out of ideas. New version checks for kernel version and bails on kernels lower than 5.x. I shall try and see if I can find the more precise kernel version where this was fixed. Meanwhile, would the coarse check like this work, if I could not find a more precise version?

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

PR: https://git.openjdk.java.net/jdk/pull/3415