get memory limit issues

[kannar]

Bug Report

What happened:

I've been running a ceph container version for years, and due to recent changes in cgroups/kernel I think the following issue:

cat: /sys/fs/cgroup/memory/memory.limit_in_bytes: No such file or directory                                                                                                                                                                                                                                                                                                                    
cat: /sys/fs/cgroup/memory/memory.usage_in_bytes: No such file or directory                                                                                                                                                                                                                                                                                                                    
2023-06-07 12:38:17  /opt/ceph-container/bin/entrypoint.sh: Found 0MB of available memory (0 bytes)                                                                                            
2023-06-07 12:38:17  /opt/ceph-container/bin/entry point.sh: osd_memory_target (-50MB) is too small, cannot tune memory.

Which is coming from get_available_ram in common_functions.sh is preventing the ceph container from starting.

What you expected to happen:

Start the container.

Environment:

• OS (e.g. from /etc/os-release):

NAME="Exherbo"
PRETTY_NAME="Exherbo Linux"
ID=exherbo
ANSI_COLOR="0;32"
HOME_URL="https://www.exherbo.org/"
SUPPORT_URL="irc://irc.libera.chat/#exherbo"
BUG_REPORT_URL="https://gitlab.exherbo.org/"

• Kernel (e.g. uname -a):

Linux pond 6.3.2+ #49 SMP PREEMPT_DYNAMIC Sun May 14 14:45:39 CEST 2023 x86_64 GNU/Linux

• Docker version (e.g. docker version):

Docker version 20.10.23, build 20.10.23

• Ceph version (e.g. ceph -v):

v6.0.3-stable-6.0-pacific-centos-8