stderr.log filling up with "Cgroups returning success file" messages

[JosKlever]

I just found out that on my webserver (Almalinux 8, DirectAdmin, OpenLiteSpeed) the file /var/log/https/stderr.log is 1.4 GB (4 years of data) and it appears to contain almost only lines with Cgroups returning success file: /sys/fs/cgroup/user.slice/ like:

2025-07-05 17:53:28.236030 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1123.slice/litespeed-exec.scope/cgroup.procs, pid: 1025195
2025-07-05 17:53:31.591079 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1151.slice/litespeed-exec.scope/cgroup.procs, pid: 1025391
2025-07-05 17:54:07.838833 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1014.slice/litespeed-exec.scope/cgroup.procs, pid: 1027899
2025-07-05 17:54:17.386850 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1066.slice/litespeed-exec.scope/cgroup.procs, pid: 1028448
2025-07-05 17:54:24.303850 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1233.slice/litespeed-exec.scope/cgroup.procs, pid: 1029005
2025-07-05 17:54:24.422781 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1236.slice/litespeed-exec.scope/cgroup.procs, pid: 1029008
2025-07-05 17:54:28.215052 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1168.slice/litespeed-exec.scope/cgroup.procs, pid: 1029198
2025-07-05 17:54:39.507537 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1112.slice/litespeed-exec.scope/cgroup.procs, pid: 1029760
2025-07-05 17:54:40.241826 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1042.slice/litespeed-exec.scope/cgroup.procs, pid: 1029944
2025-07-05 17:54:52.633911 Cgroups returning success file: /sys/fs/cgroup/user.slice/user-1177.slice/litespeed-exec.scope/cgroup.procs, pid: 1030708

I found that Cgoups might have to do something with tha cgi extension from OLS (logs are generated here). On my new server (Almalinux 10, DA, OLS) it's giving me the same lines.

What is causing these messages? How can we stop it?

And why isn't this log file rotated?