[jdk11u-dev] RFR: 8239785: Cgroups: Incorrect detection logic on old systems in hotspot

[Jonathan Dowland]

On Fri, 25 Mar 2022 10:17:45 GMT, Jonathan Dowland <jdowland at openjdk.org> wrote:

> This is a backport of 8239785 for jdk11u. The dependent backports have now all been integrated.
> 
> This PR replaces #881 which was stuck with a dependency on a superseded dependent PR.
> 
> It's not clean, but the only conflict was the copyright line in the
> comment header for src/hotspot/share/prims/whitebox.hpp.
> 
> I'm checking jtreg tests in test/hotspot/jtreg/containers on a mixture of cgroup v1 and v2 systems now.
> 
> ---------
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Testing notes:

On a cgroups v2 system with glibc 2.33, specifying `-Djdk.test.docker.image.version=hirsute` (the version of ubuntu with a matching libc version),  8 tests pass; 1 fails - containers/cgroup/PlainRead.java - which is expected (to be fixed in backport of [JDK-8278951](https://bugs.openjdk.java.net/browse/JDK-8278951))

Running tests on a cgroups v1 system now.

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PR: https://git.openjdk.java.net/jdk11u-dev/pull/946