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Re: commit: ldap/servers/slapd connection.c daemon.c proto-slap.h syncrepl.c

Howard Chu wrote:
Howard Chu wrote:
Howard Chu wrote:
For reference, the peak throughput with back-null on the previous code was
only 7,800 auths/sec (with 8 client threads). With this patch it's 11,140
auths/sec. In both cases the throughput declines as more client threads are
used. (Compare to 35,553 auths/sec for the same machine running Linux, and no
drop in throughput all the way up to hundreds/thousands of connections.)

Re-running on Linux with a non-optimized build, peaked at 40,101 auths/sec. (I
guess HEAD has sped up a bit more in the past week or so...)

OK, this is odd. The code compiled without optimization peaks at 40K auths/sec at around 124-132 client threads. The code compiled with -O2 peaks at 37K sec at around 128 client threads.

The -O2 build is faster from about 4 to 24 client threads. From 28 on up, the nonoptimized code is faster at every load level. I was originally using gcc 4.1.2 but I'm seeing the same result now using gcc 4.2.2. Also, slapd is only configured with 8 worker threads in all of these tests. Strange that whatever optimizations the compiler has generated speeds things up for lighter load, but works against it under heavier load.
-- 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/