I may have another data point w.r.t this ITS. I tried replicating this ITS by: setting up a slapd based on test003-search config plus 100,000 additional entries similar to the other OpenLDAPperson test entries. running 20+ simultaneous instances of the test003 search tests I see a definite memory growth in the server.
After the test run, according to libumem transaction logs there is about 600k lost memory in leaks (in my case). BUT the leaks are not lost cache entries or other obvious malloc/free errors.
According to libumem the "leaks" are all 4k - 16k chunks of MMAP memory allocated to thread stacks associated with threads 11 - 14.
I plan to investigate further. libumem may be reporting that there are no leaks, but instead that certain threads have significant thread stack growth under heavy activity. Alternately the threads may be terminating, resulting in loss of thread stack memory and later being restarted multiple times resulting in multiple thread stack leaks. (I am not sure yet which situation is the correct one).
Either situation may produce an unaccounted for memory growth that may not be exposed via normal debugging malloc techniques because the memory loss does not seem to be heap related.
At the end of my test threads 11-14 were not terminated. I believe this may imply significant thread stack growth not 'leakage'.
I will provide more info as I get it. I hope this helps in resolving this ITS.
Doug.