The sequence of things that happen in the execution of a program.

Overhead

  • CPU trace tools introduce a 20x slowdown
  • Timestamps at function calls introduce a 1.2-1.5x slowdown
  • Timestamp of SYS CALLS introduce < 1% slowdown
  • Valgrind: 100x slowdown since it checks every memory read and write for validity
  • Disk tracing is pretty minimal
  • The trace itself also takes up space, we need to be a bit careful about what we include in our trace information.