The OpenJDK folks have quite a long and storied history of trying to do this right and still generally recommend that if you want a JVM to have the right number of CPUs, you should set the relevant parameter yourself (-XX:ActiveProcessorCount). This is basically the same advice as Go folks telling you to set GOMAXPROCS yourself.
The problem is not just cgroups v1 vs cgroups v2 or the stability of cgroupfs, but also of CPU "shares" vs "limits", the different tunables for different Linux schedulers, the effective limits under hierarchical cgroups, etc.
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The OpenJDK folks have quite a long and storied history of trying to do this right and still generally recommend that if you want a JVM to have the right number of CPUs, you should set the relevant parameter yourself (-XX:ActiveProcessorCount). This is basically the same advice as Go folks telling you to set GOMAXPROCS yourself.
The problem is not just cgroups v1 vs cgroups v2 or the stability of cgroupfs, but also of CPU "shares" vs "limits", the different tunables for different Linux schedulers, the effective limits under hierarchical cgroups, etc.