rough estimate of kadmin addprinc performance?

[Nico Williams]

On Tue, Aug 14, 2012 at 2:58 PM, Chris Hecker <checker at d6.com> wrote:
> I just tested creation with randkey for the sake of completeness (I need
> the passwords), and yeah, it looks like this:
>
> CPU
> 11%       slapd
> 4%       kadmind
>
> but, slapd is 97% DSK, so I guess it's the fsync's.  It's basically the
> same speed (10 ank/sec), which makes sense, since the previous test with
> passwords wasn't 100% on the CPU, so it was disk bound as well on ldap.
>
> Deletes are also 10/sec.

Trace slapd to check how many fsync()s per-write it's doing.  I
suspect it's doing more than a single fsync() per-write operation --
assuming that you have a typical 7200rpm disk it must be doing quite a
few fsync()s per-op!  You might research alternative slapd backends
and/or using SSDs.  An enterprise-quality SSD (that can safely flush
buffers to flash under power failure conditions) would probably net
you a ~100x performance increase.

Nico
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