Hi Plaban,
Have your Search Datasource and User Details Datasource as LDAP/AD.
Set up 2051 parameter as YES
Don't run Repository Object Sync for LDAP/AD
Once you have the above configuration, try to search for the users from LDAP/AD which will be real-time.
May i know why you want your datasource as LDAP but dont want search to be realtime?
Regards,
Madhu.