cvs commit: src/tools/sched schedgraph.py

[Jeff Roberson]

jeff        2007-01-24 21:19:56 UTC

  FreeBSD src repository

  Modified files:
    tools/sched          schedgraph.py 
  Log:
   - Add a horrible bit of code to detect tsc differences between processors.
     This only works if there is no significant drift and all processors are
     running at the same frequency.  Fortunately, schedgraph traces on MP
     machines tend to cover less than a second so drift shouldn't be an issue.
   - KTRFile::synchstamp() iterates once over the whole list to determine the
     lowest tsc value and syncs adjusts all other values to match.  We assume
     that the first tick recorded on all cpus happened at the same instant to
     start with.
   - KTRFile::monostamp() iterates again over the whole file and checks for
     a cpu agnostic monotonically increasing clock.  If the time ever goes
     backwards the cpu responsible is adjusted further to fit.  This will
     make the possible incorrect delta between cpus as small as the shortest
     time between two events.  This time can be fairly large due to sched_lock
     essentially protecting all events.
   - KTRFile::checkstamp() now returns an adjusted timestamp.
   - StateEvent::draw() detects states that occur out of order in time and
     draws them as 0 pixels after printing a warning.
  
  Revision  Changes    Path
  1.11      +112 -28   src/tools/sched/schedgraph.py