Howard Chu wrote:
The write rate is pretty slow, as we already knew. I frankly don't see it improving very much, given the single-writer nature of MDB.
I guess "slow" is relative. My previous modrate tests didn't touch any indices. I've added entryCSN,entryUUID eq indexing to the config (since that's common for a syncrepl environment) and gotten much different results.
Basically for back-hdb there's a continuous stream of deadlocks from updating the entryCSN index. This pushes the maximum mod rate down to only 3400/sec. With this configuration back-mdb was actually faster, at 3800/sec.
With accesslog thrown into the mix, back-mdb drops to 2500/sec while back-hdb drops to 1700/sec. So for any realistic scenario, back-mdb beats back-hdb all around.
-- -- Howard Chu CTO, Symas Corp. http://www.symas.com Director, Highland Sun http://highlandsun.com/hyc/ Chief Architect, OpenLDAP http://www.openldap.org/project/