Jim works in the Systems group, with a primary focus on systems performance. Jim’s work includes internal performance-related projects, as well as working with Oracle customers on diagnosing performance issues on production systems. Jim has 30 years of experience in the computer industry, including 19 years with Sun Microsystems prior to the acquisition by Oracle. Jim has used DTrace extensively for his performance work since it was first introduced in Solaris 10 and has taught Solaris performance analysis and DTrace for many years. Jim coauthored the first and second editions of Solaris Internals (McDougall and Mauro, 2006) and Solaris Performance and Tools (McDougall, Mauro, and Gregg, 2006) and has written numerous articles and white papers on various aspects of Solaris performance and internals.