  We show how to quantify scalability with the Universal Scalability Law (USL)
by applying it to performance measurements of memcached, J2EE, and Weblogic on
multi-core platforms. Since commercial multicores are essentially black-boxes,
the accessible performance gains are primarily available at the application
level. We also demonstrate how our methodology can identify the most
significant performance tuning opportunities to optimize application
scalability, as well as providing an easy means for exploring other aspects of
the multi-core system design space.
