pidns: virtualize pid_max¶
This feature makes kernel.pid_max
sysctl be per pid namespace
(instead of a global sysctl by default).
Q: Why do we need this feature at all? A:
historically is was implemented to support 32bit containers (pids with the value greater than 2^32 make 32bit userspace go mad)
this feature is needed for Containers online migration: if someone tries to migrate a process with pid XXX to the Hardware Node with pid_max < XXX, the migration will fail without iper-pidns pid_max support