TNL::PerformanceCounters Struct Reference

Performance counter for measuring CPU cycles. More...

#include <TNL/PerformanceCounters.h>

Public Member Functions
	PerformanceCounters ()
	Constructor with no parameters.
unsigned long long int	getCPUCycles () const
	Returns the number of CPU cycles (machine cycles) elapsed on this timer.
void	reset ()
	Reset counters.
void	start ()
	Starts counters.
void	stop ()
	Stops (pauses) the counters but do not set them to zeros.
bool	writeLog (Logger &logger, int logLevel=0) const
	Writes a record into the logger.

Detailed Description

Performance counter for measuring CPU cycles.

The counter can be paused by calling stop and start methods and reseted by calling reset.

Example

#include <iostream>
#include <chrono>
#include <thread>
 
#include <TNL/PerformanceCounters.h>
 
int
main()
{
   const int milliseconds = 0.5e3;
   TNL::PerformanceCounters performanceCounters;
   performanceCounters.start();
   std::this_thread::sleep_for( std::chrono::milliseconds( milliseconds ) );
   performanceCounters.stop();
 
   std::cout << "Elapsed CPU cycles: " << performanceCounters.getCPUCycles() << std::endl;
   performanceCounters.reset();
   std::cout << "CPU cycles after reset: " << performanceCounters.getCPUCycles() << std::endl;
}

Output

Elapsed CPU cycles: 1800256694
CPU cycles after reset: 0

Member Function Documentation

getCPUCycles()

unsigned long long int TNL::PerformanceCounters::getCPUCycles ( ) const

inline

Returns the number of CPU cycles (machine cycles) elapsed on this timer.

CPU cycles are counted by adding the number of CPU cycles between start and stop methods together.

start()

void TNL::PerformanceCounters::start ( )

inline

Starts counters.

This method can be used also after using the stop method. The counters then continue the measuring.

writeLog()

bool TNL::PerformanceCounters::writeLog ( Logger & logger, int logLevel = 0 ) const

inline

Writes a record into the logger.

Parameters

logger	Name of Logger object.
logLevel	A non-negative integer recording the log record indent.

Example

#include <iostream>
#include <chrono>
#include <thread>
 
#include <TNL/Timer.h>
#include <TNL/Logger.h>
 
int
main()
{
   const int milliseconds = 0.5e3;
   TNL::Timer time;
   time.start();
   std::this_thread::sleep_for( std::chrono::milliseconds( milliseconds ) );
   time.stop();
 
   TNL::Logger logger( 50, std::cout );
   time.writeLog( logger, 0 );
}

Output

| Real time:                             0.500066 |
| CPU time:                                 9e-06 |

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The documentation for this struct was generated from the following files:

• src/TNL/PerformanceCounters.h
• src/TNL/PerformanceCounters.hpp