anchor.diff:  (define-event :real-time "Real time")
   (define-event :user-time "User time")
   
  -;;;; GC runs
  -
   (define-event :gc-count "GC count")
  -
  -;;;; Measuring System Info
   
   (defcstruct timeval
     (sec :long)
  
positive.code: (defun get-resource-usage ()
    (with-foreign-object (rusage 'rusage)
      (getrusage +rusage-self+ rusage)
      (with-foreign-slots ((stime majflt nvcsw nivcsw) rusage rusage)
        (with-foreign-slots ((sec usec) stime timeval)
          (values (+ (* sec 1000000000) (* usec 1000))
                  majflt nvcsw nivcsw)))))
  
  (define-event :system-time "System time")
  
  ;;;; Profiling
  
  
  ;;;; Interface
  
  
negative.code:           (setq user-nsec-total (- (papi-get-virt-nsec) user-nsec-total))
            (papi-accum handle mutator-values)))
        (papi-stop handle (null-pointer))
        (multiple-value-bind (stime reclaims faults vcsw ivcsw)
            (get-resource-usage)
          (setq system-usec-total (- stime system-usec-total))
          (setq page-reclaims-total (- reclaims page-reclaims-total))
          (setq page-faults-total (- faults page-faults-total))
          (setq vcsw-total (- vcsw vcsw-total))
          (setq ivcsw-total (- ivcsw ivcsw-total)))
        ;; Aggregate measurements.
        (let ((hw-event-results
               (loop for event in (events-of event-set) and i from 0 collect
  