Tuning Linux for Postgresql - Database failed to start

Hello,
I have a Postgresql Database cluster.
Version: 14.2
OS: Oracle Linux 8

I tried to follow the link to optimize the server.
https://www.enterprisedb.com/blog/tuning-red-hat-enterprise-linux-family-postgresql

Unfortunately, after rebooting the database is not starting anymore. I know
the HINT is straightforward but I am not able to see what the reason could
be.

Any advice would be appreciated.

-- Unit postgresql-14.service has begun starting up.
May 10 22:10:40 postgersdb.localdomain postmaster[1612]: 2022-05-10
22:10:40.047 CEST [1612] FATAL: could not map anonymous shared memory:
Cannot allocate memory
May 10 22:10:40 postgersdb.localdomain postmaster[1612]: 2022-05-10
22:10:40.047 CEST [1612] *HINT: This error usually means that PostgreSQL's
request for a shared memory segment exceeded available memory,>*
May 10 22:10:40 postgersdb.localdomain postmaster[1612]: 2022-05-10
22:10:40.048 CEST [1612] LOG: database system is shut down
May 10 22:10:40 postgersdb.localdomain systemd[1]: postgresql-14.service:
Main process exited, code=exited, status=1/FAILURE
May 10 22:10:40 postgersdb.localdomain systemd[1]: postgresql-14.service:
Failed with result 'exit-code'.
-- Subject: Unit failed
-- Defined-By: systemd
-- Support: https://support.oracle.com