Re: static user probe performance

[Stan Cox <scox at redhat dot com>]

Output massaged with an awk script:

not run with stap
user time
      no volatile no semaphore 1.07
      no volatile semaphore 1.11
      volatile semaphore 1.16
      volatile no semaphore 1.18
system time
      volatile no semaphore 0.03
      no volatile semaphore 0.03
      volatile semaphore 0.04
      no volatile no semaphore 0.05
elapsed time
      volatile no semaphore 38.18
      no volatile no semaphore 48.02
      volatile semaphore 51.66
      no volatile semaphore 60.23

* volatile refers to: do the user probe arguments use volatile
  semaphore refers to: are the user probes guarded by a semaphore

run with stap
user time
      no volatile no semaphore 3.49
      no volatile semaphore 3.56
      volatile semaphore 3.62
      volatile no semaphore 3.7
system time
      volatile semaphore 58.34
      no volatile semaphore 58.51
      volatile no semaphore 58.68
      no volatile no semaphore 58.72
elapsed time
      volatile semaphore 1858.71
      no volatile no semaphore 1865.68
      volatile no semaphore 1873.07
      no volatile semaphore 1878.09