MB-10734: rounded ops/sec

Change-Id: I3311f7d454326305b0c3c6d3e7d67182904882d2
Reviewed-on: http://review.couchbase.org/39536
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>
Tested-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>