Re: hdb search performance

tamarin p wrote:

2008/8/26 Howard Chu <hyc@symas.com mailto:hyc@symas.com>

Also check your dncachesize, the DN cache tends to be the critical
element in back-hdb's performance. Still, if the filter attributes
are indexed it should not be so slow...

Wasn't aware of this parameter, and couldn't find it in the administrator guide. Tried setting it to about the same as cachesize but it doesn't seem to have a huge effect. The first time the search runs after server-start-up, it still takes minutes to complete. Interestingly enough, CPU usage is very low during this time, below 10%, and even below 5% most of the time. iostat reports about 3.4% iowait.

There is this that needs updating:

http://www.openldap.org/doc/admin24/tuning.html#Performance%20Factors

and "man slapd-bdb"