commit c1a2a4bccbaf53b61b0510a64503b802ccfd7388
Author: Ralf Haferkamp <rhafer@suse.com>
Date:   Wed May 6 20:19:06 2020 +0200

    replication: Avoid expensive nested loop when loglevel below INFO
    
    handler() goes into a nested for loop to figure out whether the
    entry read from LDAP differs from the one it got from the cache.
    The purpose of that seems to be to log a message (at "INFO" level)
    when they differ.
    
    That nested for loop can be every expensive. E.g. for very large
    groups. (We ran into this with a group with roughly 100000 values
    in the memberUid and uniqueMember attributes).
    
    This patch skips the loop when the currently set loglevel is
    below "INFO". It might make sense only go even further and to the
    logs only and "DEBUG" level. (Or skip the checks if the number of
    attribute values is beyond a certain size).

diff --git a/management/univention-directory-replication/replication.py b/management/univention-directory-replication/replication.py
index 97d69e7a80..0e380c3b41 100644
--- a/management/univention-directory-replication/replication.py
+++ b/management/univention-directory-replication/replication.py
@@ -829,30 +829,31 @@ def handler(dn, new, listener_old, operation):
 		if not isinstance(l, LDIFObject):
 			old = getOldValues(l, dn)
 
-			# Check if both entries really match
-			match = 1
-			if len(old) != len(listener_old):
-				ud.debug(ud.LISTENER, ud.INFO, 'replication: LDAP keys=%s; listener keys=%s' % (list(old.keys()), list(listener_old.keys())))
-				match = 0
-			else:
-				for k in old:
-					if k in EXCLUDE_ATTRIBUTES:
-						continue
-					if k not in listener_old:
-						ud.debug(ud.LISTENER, ud.INFO, 'replication: listener does not have key %s' % (k,))
-						match = 0
-						break
-					if len(old[k]) != len(listener_old[k]):
-						ud.debug(ud.LISTENER, ud.INFO, 'replication: LDAP and listener values diff for %s' % (k,))
-						match = 0
-						break
-					for v in old[k]:
-						if v not in listener_old[k]:
-							ud.debug(ud.LISTENER, ud.INFO, 'replication: listener does not have value for key %s' % (k,))
+			if ud.get_level(ud.LISTENER) >= ud.INFO:
+				# Check if both entries really match
+				match = 1
+				if len(old) != len(listener_old):
+					ud.debug(ud.LISTENER, ud.INFO, 'replication: LDAP keys=%s; listener keys=%s' % (list(old.keys()), list(listener_old.keys())))
+					match = 0
+				else:
+					for k in old:
+						if k in EXCLUDE_ATTRIBUTES:
+							continue
+						if k not in listener_old:
+							ud.debug(ud.LISTENER, ud.INFO, 'replication: listener does not have key %s' % (k,))
+							match = 0
+							break
+						if len(old[k]) != len(listener_old[k]):
+							ud.debug(ud.LISTENER, ud.INFO, 'replication: LDAP and listener values diff for %s' % (k,))
 							match = 0
 							break
-			if not match:
-				ud.debug(ud.LISTENER, ud.INFO, 'replication: old entries from LDAP server and Listener do not match')
+						for v in old[k]:
+							if v not in listener_old[k]:
+								ud.debug(ud.LISTENER, ud.INFO, 'replication: listener does not have value for key %s' % (k,))
+								match = 0
+								break
+				if not match:
+					ud.debug(ud.LISTENER, ud.INFO, 'replication: old entries from LDAP server and Listener do not match')
 		else:
 			old = listener_old