Howard, I tried bigger caches but I do not have enough memory to apply them. This was the reason I only tried the dncachesize to speed up search queries. I also have this same database running in a old openldap version(2.1.30) even with a little more records on it. In this version, as I understand, there isn't any cache at openLDAP but only at BDB. See how it is behaving in terms of memory and CPU from the openLDAP 2.1.30: PID USER PRI NI SIZE RSS SHARE STAT %CPU %MEM TIME CPU COMMAND 3651 root 24 0 136M 135M 126M S 0.0 1.1 0:00 1 slapd See a really small memory consumption and I really reasonable performance. The only issue I have with this version is about the replication mechanism which I would like to increase its availability using syncrepl unless slurpd. The problem is that for version after 2.1 looks like we need to have enough memory to cache all database since there are many situations where slapd appear increase CPU or memory usage and considerably reduce performance. I tried to remove from slapd.conf any cache constraint seeing if the previous version performance directly from disk reads would be reproduced. I saw some good startup, like 500 returns per second, but after sometime slapd hanged and did not return any more records to ldapseach. Also it consumed all 4 CPUs : PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 4409 ldap 15 0 400m 183m 132m S 400 1.5 27:22.70 slapd And even after I stop the ldapsearch the CPU consumption continues consuming all CPUs processing. I believe it entered in a dead loop. I do not have a heavily load system but based in records and DBs I have some memory resource constraints. I also tried some smaller caches, like : cachesize 500000 dncachesize 500000 idlcachesize 500000 cachefree 10000 But it also hangs the search after sometime. I was wondering if there is a way to run slapd without cache, reading from disk(like first time read to insert record in cache), what is enough for small/medium systems in terms of consulting. In this way I could use the behavior as the 2.1.30 system and the new syncrepl replication. Thanks a lot ! Rodrigo. Howard Chu wrote: