gko::Timer Class Reference

Represents a generic timer that can be used to record time points and measure time differences on host or device streams. More...

#include <ginkgo/core/base/timer.hpp>

Inheritance diagram for gko::Timer:

Public Member Functions
time_point	create_time_point ()
	Returns a newly created time point. More...
virtual void	record (time_point &time)=0
	Records a time point at the current time.
virtual void	wait (time_point &time)=0
	Waits until all kernels in-process when recording the time point are finished.
std::chrono::nanoseconds	difference (time_point &start, time_point &stop)
	Computes the difference between the two time points in nanoseconds. More...
virtual std::chrono::nanoseconds	difference_async (const time_point &start, const time_point &stop)=0
	Computes the difference between the two time points in nanoseconds. More...

Static Public Member Functions
static std::unique_ptr< Timer >	create_for_executor (std::shared_ptr< const Executor > exec)
	Creates the timer type most suitable for recording accurate timings of kernels on the given executor. More...

Detailed Description

Represents a generic timer that can be used to record time points and measure time differences on host or device streams.

To keep the runtime overhead of timing minimal, time points need to be allocated beforehand using Timer::create_time_point:

auto begin = timer->create_time_point();
auto end = timer->create_time_point();
// ...
timer->record(begin);
run_expensive_operation();
timer->record(end);
auto elapsed = timer->difference(begin, end);

Member Function Documentation

create_for_executor()

static std::unique_ptr<Timer> gko::Timer::create_for_executor ( std::shared_ptr< const Executor >  exec )

static

Creates the timer type most suitable for recording accurate timings of kernels on the given executor.

Parameters

exec	the executor to create a Timer for

Returns

CpuTimer for ReferenceExecutor and OmpExecutor, CudaTimer for CudaExecutor, HipTimer for HipExecutor or DpcppTimer for DpcppExecutor.

create_time_point()

time_point gko::Timer::create_time_point

(

)

Returns a newly created time point.

Time points may only be used with the timer they were created with.

difference()

std::chrono::nanoseconds gko::Timer::difference	(	time_point &	start,
		time_point &	stop
	)

Computes the difference between the two time points in nanoseconds.

The function synchronizes with stop before computing the difference.

Parameters

start	the first time point (earlier)
end	the second time point (later)

Returns

the difference between the time points in nanoseconds.

difference_async()

virtual std::chrono::nanoseconds gko::Timer::difference_async ( const time_point &  start, const time_point &  stop  )

pure virtual

Computes the difference between the two time points in nanoseconds.

This asynchronous version does not synchronize itself, so the time points need to have been synchronized with, i.e. timer->wait(stop) needs to have been called. The version is intended for more advanced users who want to measure the overhead of timing functionality separately.

Parameters

start	the first time point (earlier)
end	the second time point (later)

Returns

the difference between the time points in nanoseconds.

Implemented in gko::DpcppTimer, gko::HipTimer, gko::CudaTimer, and gko::CpuTimer.

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The documentation for this class was generated from the following file:

• ginkgo/core/base/timer.hpp