Anybody know what this means? bdb_idl_delete_key: c_del id failed: DB_LOCK_DEADLOCK

Anybody know what this is about and why it keeps repeating in the Open Directory of LDAP log?

I thought a clean install of 10.10.3/4.1 server would fix it but it hasn't. Came back after importing users and groups. Have to import users as they are tied to a calendar server so need the same UUID.

DNS resolving forward and reverse.

No other services other then Open Directory running.

Thanks in advance if any suggestions.

On restart this is how it begins..... xxx.xx.com = name I changed to hide company name.....

slapd[245]: @(#) $OpenLDAP: slapd 2.4.28 (Feb 24 2015 21:45:59) $

root@osx202.apple.com:/BinaryCache/OpenLDAP/OpenLDAP-499.32.4~1/Objects/servers/slapd

Jun 27 21:40:30 xxx.xx.com slapd[245]: daemon: SLAP_SOCK_INIT: dtblsize=8192

Jun 27 21:40:30 xxx.xx.com slapd[245]: TLS: OPENDIRECTORY_SSL_IDENTITY identity preference overrode configured olcTLSIdentity "APPLE: xxx.xx.com"

Jun 27 21:40:30 xxx.xx.com slapd[245]: slap_add_listener: opened additional listener 'ldaps:///'

Jun 27 21:40:31 xxx.xx.com slapd[245]: bdb_monitor_db_open: monitoring disabled; configure monitor database to enable

Jun 27 21:40:31 xxx.xx.com slapd[245]: slapd starting

Jun 27 21:40:31 xxx.xx.com slapd[245]: daemon: posting com.apple.slapd.startup notification

Jun 27 21:40:38 xxx.xx.com slapd[245]: => bdb_idl_delete_key: c_del id failed: DB_LOCK_DEADLOCK: Locker killed to resolve a deadlock (-30994)

Jun 27 21:40:38 xxx.xx.com slapd[245]: conn=1426 op=2: attribute "entryCSN" index delete failure

Jun 27 21:40:38 xxx.xx.com slapd[245]: => bdb_idl_insert_key: c_get failed: DB_LOCK_DEADLOCK: Locker killed to resolve a deadlock (-30994)

Jun 27 21:40:38 xxx.xx.com slapd[245]: conn=1426 op=4: attribute "entryCSN" index add failure

Jun 27 21:40:38 xxx.xx.com slapd[245]: => bdb_idl_insert_key: c_put id failed: DB_LOCK_DEADLOCK: Locker killed to resolve a deadlock (-30994)