Description of problem:
As mentioned in the RHDS docs [1], disabling the access log buffering can have a severe impact on performance:
https://access.redhat.com/documentation/en-us/red_hat_directory_server/11/html-single/configuration_command_and_file_reference/index#cnconfig-nsslapd_accesslog_logbuffering_Log_Buffering

There should be also a warning message when disabling nsslapd-accesslog-logbuffering ( CLI or Console ).

The performance impact can be tremendous.
A customer was running a performance testing with ldclt and for some reason the buffering was disabled.
Performance was pretty bad compared to RHDS 10 ( which has the buffering enabled ).
We've spent a couple of days to find the culprit ( after tuning caches, worker threads, ... )

RHDS 11:

• nsslapd-accesslog-logbuffering: off
  Global average rate: 3627.80/thr (604.63/sec), total: 36278

• nsslapd-accesslog-logbuffering: on
  Global average rate: 97150.60/thr (16191.77/sec), total: 971506

Version-Release number of selected component (if applicable):
$ cat /etc/redhat-release
Red Hat Enterprise Linux release 8.8 (Ootpa)
$
$ rpm -qa | grep 389-ds
389-ds-base-1.4.3.31-11.module+el8dsrv+17815+4f95348d.x86_64
389-ds-base-libs-1.4.3.31-11.module+el8dsrv+17815+4f95348d.x86_64
cockpit-389-ds-1.4.3.31-11.module+el8dsrv+17815+4f95348d.noarch
$

How reproducible:
Always.

Steps to Reproduce:
Disable nsslapd-accesslog-logbuffering

Actual results:
No warning message when disabling the buffering via CLI or Console.

Expected results:
Add a warning message about the performance degradation.

Additional info:
DB files and log files were under separate partitions.
Performance would likely be worse if using the same partition.