Yep, that helped. Raising rx-usecs from default 20 to 1000, and rx-frames from
default 5 to 100, I'm getting 43k auths/sec with back-null (in 4 separate
thread pools) and the core fielding the interrupts is only about 80% busy now
instead of 100%. I'm afraid my load generators may be maxed out now, because I
can't seem to drive up the load on the server any higher even though there's
more idle CPU.
The current code in HEAD (with only 1 thread pool) is reaching 36k auths/sec
with back-null, so it's actually not far off from my experimental peak rate.
Considering that HEAD was at 25k/sec last week (and now in 2.4.6) that's
pretty decent.
With back-bdb and 1 million users I'm getting 26.1k/sec with plaintext
passwords (up from 19.3k/sec last week). With {SSHA} passwords that drops to
25.7k/sec (~1.5% difference).
I have to put this tinkering on hold for a bit, to run some authrate tests
against ActiveDirectory on this machine (using W2K3sp2 X64). Later on we'll do
a W2K3 OpenLDAP build for comparison as well. Should be entertaining...
--
-- Howard Chu
Chief Architect, Symas Corp. http://www.symas.com
Director, Highland Sun http://highlandsun.com/hyc/
Chief Architect, OpenLDAP http://www.openldap.org/project/