--On Wednesday, March 04, 2009 1:55 PM -0500 John Morrissey jwm@horde.net wrote:
I upgraded one of our consumers to 2.4.15 recently, from RE24 as of 20090113. Its configuration stayed the same, save for bumping the BDB cache size from 256MB to 2GB.
After a few hours of uptime, slapd suddenly begins consuming enormous amounts of CPU (a three- to four-fold increase over less than a few minutes, and is sustained until slapd is restarted).
A backtrace (below) shows many threads waiting on a mutex in bdb_cache_*().
This is with BDB 4.7 (with all patches applied) on Debian lenny. 'db_stat -c' output is below (and looks sane), in case that's useful. Thinking thread contention, I bumped the worker thread count (slapd.conf threads directive) down from 32 to 8, which has made no difference.
Interseting. I've seen this sort of CPU usage issue with OpenLDAP 2.3/BDB4.2.52 on Ubuntu 8. Do you know how BDB 4.7 was built? I.e., specifically, did it have the:
--enable-posixmutexes --with-mutex=POSIX/pthreads
options enabled?
Also, are you using a shared memory key? I've found that has a significant (positive) impact with BDB 4.7 on linux boxes.
--Quanah
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Quanah Gibson-Mount Principal Software Engineer Zimbra, Inc -------------------- Zimbra :: the leader in open source messaging and collaboration