slow shutdowns

I'm running a pretty large slapd 2.3.23 (3G-5G or so) and shutdown is taking anywhere from twenty minutes to an hour. (I'm still waiting for a shutdown and hoping for an hour)

I was just wondering what exactly was happening. I suspect that it's something in bdb_db_close(), but I'm not sure what's really going on since truss is just sitting around and prstat reports the pid in sleep.

My guess is that it's walking the entire cache and free-ing it, but I would expect the memory to change or the truss to return free's in that case. Any ideas? My last log messages are: daemon: shutdown requested and initiated. slapd shutdown: waiting for 0 threads to terminate

Thanks, _Matt