/sys/fs/cgroup/pids/system.slice/system-postgresql.slice
Directories:

• /sys/fs/cgroup/pids/system.slice
• /sys/fs/cgroup/pids/system.slice/system-postgresql.slice/postgresql@11-main.service

Files:

• cgroup.procs
• pids.current
• pids.events
• tasks
• notify_on_release
• pids.max
• cgroup.clone_children