[bug] get_cpus is not supporting cgroup2

The current detection of https://github.com/conan-io/conan/blob/1.46.2/conans/client/tools/oss.py#L36-L39 seems no longer applicable in case of cgroup2 as the /sys/fs/cgroup/cpu/cpu.cfs_quota_us and /sys/fs/cgroup/cpu/cpu.cfs_period_us are replaced by /sys/fs/cgroup/cpu.max (in case of docker executed with --cpus).

There could be checked if cgroup2 is active for example by checking for existence of /sys/fs/cgroup/cgroup.controllers file and based on that the values for quota and period could be taken from cpu.max file.

[maikelvdh]

@MariaMozgunova the $MAX in cpu.max is basically the same as quota before, so you can use that to calculate in this case the same.

[memsharded]

Hi @MariaMozgunova

Yes, there are many tests that require to have some tools installed, like different build systems. You can check the conftest.py file, it contains a json declarative syntax to enable/disable/configure required tools. You can write your own confuser_test.py overriding and disabling some tools.

If you are going to touch such a very specific tool, I’d recommend looking in the unittest and integration test folders, the one that are covering the existing functionality and just run them (the folder or the file with pytest <path/to/folder>. It is going to be much faster and convenient. Don’t worry, our CI run all tests for PRs.