I was performing an ldapmodify ldif import today on my test ldap server.
We're migrating from NIS, but while NIS is still live, I periodically
sync the NIS passwords into LDAP by using the PADL migration tools to
dump the NIS passwd/shadow into an ldif and then using ldapmodify to load
into LDAP. We have ~ 1000 users. This morning, it hung on a particular
user, to where slapd was taking up 99.9% CPU and not responding to any
other requests. It required a kill -9. I repeated the behavior and it
hung in the exact same spot. I removed that particular record from the
LDIF and it went a lot farther, but then hung on another account (again,
behavior that I could repeat predictably).