Hello. Since I installed the rules dedicated to dropping LDAP probe connection traces, the memory usage of my ldap server exploded. top confirms than syslog-ng is the culprit, using 60% of the available memory. Here is a weekly munin graph presenting the issue: http://www.zarb.org/~guillomovitch/memory-week.png The rules have been installed on 19th, and I restarted syslog-ng yesterday. I'm using syslog-ng 3.2.1, on mandriva 2010.0, 64 bits. Here are the exact rules used, if that matters (I couldn't try latest Balazs suggestions yet). The context-timeout for the first rule is quite low, because the probe checks every two seconds. By any chance, doesn't the second timeout, set to 0, set an illimited session expiration time ? If not the case, I'd gladly try any needed experiment, such as running syslog-ng under valgrind, to identify the leak source. -- BOFH excuse #400: We are Microsoft. What you are experiencing is not a problem; it is an undocumented feature.