Clock.cpp

/*
 * Clock.cpp
 *
 *  Created on: Jun 6, 2016
 *      Author: pschultz
 */

#include "Clock.hpp"

namespace PV {

void Clock::start_clock() {
   struct rusage r;
   struct timeval t;

   m_start = clock();

   getrusage(RUSAGE_SELF, &r);
   m_rstart = r.ru_utime.tv_sec + r.ru_utime.tv_usec * 1.0e-6;

   gettimeofday(&t, (struct timezone *)0);
   m_tstart   = t.tv_sec + t.tv_usec * 1.0e-6;
   m_tv_start = t;
#ifdef MACH_TIMER
   m_mach_start = mach_absolute_time();
#endif

#ifdef CYCLE_TIMER
   READ_CYCLE_COUNTER(cycle_start);
#endif
}

void Clock::stop_clock() {
   struct rusage r;
   struct timeval t;

   m_end = clock();

   getrusage(RUSAGE_SELF, &r);
   m_rend = r.ru_utime.tv_sec + r.ru_utime.tv_usec * 1.0e-6;

   gettimeofday(&t, (struct timezone *)0);
   m_tend   = t.tv_sec + t.tv_usec * 1.0e-6;
   m_tv_end = t;

#ifdef MACH_TIMER
   m_mach_end = mach_absolute_time();
#endif

#ifdef CYCLE_TIMER
   READ_CYCLE_COUNTER(m_cycle_end);
#endif
}

void Clock::print_elapsed(std::ostream &stream) {
   std::streamsize w = stream.width(1);
   std::streamsize p = stream.precision(2);
   stream << "     " << (float)((double)(m_end - m_start) / CLOCKS_PER_SEC)
          << " seconds elapsed (clock())\n";
   stream << "     " << (float)(m_rend - m_rstart) << " seconds elapsed (CPU)\n";
   stream << "     " << (float)(m_tend - m_tstart) << " seconds elapsed (wallclock)\n";
   stream.width(w);
   stream.precision(p);

#ifdef MACH_TIMER
   uint64_t mach_elapsed = mach_time_to_sec(m_mach_end - m_mach_start);
   stream << "Mach processor cycle time = " << (float)m_mach_elapsed << "\n";
#endif

#ifdef CYCLE_TIMER
   uint64_t cycle_elapsed = m_cycle_end - m_cycle_start;
   stream << cycle_elapsed << " cycles elapsed\n";
   stream << (float) ((double)cycle_elapsed/(double)CYCLES_PER_SEC << " seconds elapsed (cycle timer)\n";
#endif
}

#ifdef MACH_TIMER
double Clock::elapsed_time() { return mach_time_to_sec(mach_absolute_time() - mach_start); }

double Clock::mach_time_to_sec(uint64_t elapsed) {
   if (sTimebaseInfo.denom == 0) {
      // initialize (yuk, hope it isn't some stray value)
      (void)mach_timebase_info(&sTimebaseInfo);
   }

   double ms = (double)(elapsed) / 1.0e9;
   ms *= sTimebaseInfo.numer / sTimebaseInfo.denom;

   return ms;
}

#endif // MACH_TIMER

} // namespace PV