RFR: 8296125: Add a command line option to set a refresh rate of the OS cached metrics in Linux [v2]

[Severin Gehwolf]

On Wed, 2 Nov 2022 19:19:33 GMT, Thomas Stuefe <stuefe at openjdk.org> wrote:

> Maybe it is my limited understanding, but I cannot see an application that needs even sub-second reaction time to a changed container memory limit. @jerboaa what do you think?

The use-cases I know of don't rely on this hot-update mechanism. Usually, on k8s, pods/containers get re-created (i.e. restarted) on re-deployments. As far as I know, the reason why those metrics are being re-read to begin with is the existence of an [`docker update` command](https://docs.docker.com/engine/reference/commandline/update/).

With all that said, I'm +1 on trying to understand the problem better that the user reported. Unfortunately JBS is currently in maintenance so I cannot look at the bug :-(

If the user thinks, the metrics parsing code is the culprit this can get tested easily by letting them specify `-XX:-UseContainerSupport` (and possibly set the desired memory and cpu cores manually using `-XX:ActiveProcessorCount=n` and `-XX:MaxRAM=m`).

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PR: https://git.openjdk.org/jdk/pull/10918