Re: slapadd/bdb tuning newbie

[Howard Chu <hyc@symas.com>]

Gary LaVoy wrote:

 > set in slapd.conf for each of these db's respectively. I am not sure 
how
> the cachesize in slapd.conf and DB_CONFIG work with each other, if at 
> all, so I didn't want the addition of all these to be too large.

This seems to be an FAQ... The back-bdb cachesize configures the 
back-bdb entry cache; it is the number of LDAP entries that back-bdb 
will keep in memory to satisfy LDAP queries. In regard to the current 
email topic, it's worth noting that slapadd doesn't generate LDAP 
queries, and so the entry cache isn't involved. (Likewise for 
slapcat/slapindex/etc...)

> Maybe setting set_cachesize 0 500000000 0 for each would still be under 
> my total real RAM limit and help out?

It may help, yes. I would look at your db_stat info and see how the 
existing cache performed first, though.

> And, yes, the logs and the db are on the same disk. for development 
> purposes I can move them to a space on the system disk since I own root 
> on the box just to see how much improvement I can get. If it's really 
> significant I can request this for production as an exception (where app 
> teams do not have root)

If you upgrade to BDB 4.2 you can configure BDB to omit the transaction 
logs. That should help slapadd a bit, but again, you don't want to run 
slapd with that setting. You should definitely try it with the separate 
disk and see how much difference it makes.
--
  -- Howard Chu
  Chief Architect, Symas Corp.       Director, Highland Sun
  http://www.symas.com               http://highlandsun.com/hyc
  Symas: Premier OpenSource Development and Support