Hi Quanah, Thanks for the response. I finally got around to upgrading and I am still in the same boat. I am now running version 2.4.53.
# slapd -V @(#) $OpenLDAP: slapd 2.4.53 (Sep 24 2020 20:30:24) $
I have implemented delta-syncrepl as suggested. I already had stat + sync set for logging and I see nothing unusual to report - just lots of connections (across all consumers) and periodic syncrepl messages as expected.
I ran strace against slapd and didn't come up with anything that is obviously different between HDB and MDB consumers.
I then set olcLogLevel to "any" and got thousands of the following log entries: "mdb_search: scope not okay"
slapd[28595]: mdb_search: 40396 scope not okay
I am not sure what causes these log entries and if these are related to higher CPU utilization. If you have any input/suggestions on where to look next it would be much appreciated.
Regards, Paul