Measures execution time between construction and destruction. AutoTimer can output either to a std::ostream or to a spdlog::logger More...

#include <lf/base/timer.h>

Public Member Functions
	AutoTimer (std::string format=Timer::kDefaultFormat)
	Create a new AutoTimer that will report time measurements to `std::cout` when destructed.

	AutoTimer (std::ostream &stream, std::string format=Timer::kDefaultFormat)
	Create a new AutoTimer that will report to the given stream during destruction.

	AutoTimer (std::shared_ptr< spdlog::logger > logger, spdlog::level::level_enum level=spdlog::level::level_enum::info, std::string format=Timer::kDefaultFormat)
	Create a new AutoTimer that will report to the given `spdlog::logger` on destruction.

	AutoTimer (const AutoTimer &)=default

	AutoTimer (AutoTimer &&)=default

AutoTimer &	operator= (const AutoTimer &)=default

AutoTimer &	operator= (AutoTimer &&)=default

	~AutoTimer ()
	Destructor of AutoTimer, calls Report().

std::ostream &	ostream () const
	Retrieve the output stream object that was passed in the constructor.

const std::shared_ptr< spdlog::logger > &	logger () const
	Retrieve the logger that was passed in the constructor.

const std::string &	FormatString () const
	Retrieve the format string that was passed in the constructor.

void	Report ()
	Report time (wall, user, system) since construction of AutoTimer() to either a `std::ostream` or `spdlog::logger` that was passed in the constructor.

Timer::cpu_times	Elapsed () const noexcept
	Retrieve the elapsed time since the construction.

std::string	Format (std::string_view format=Timer::kDefaultFormat) const
	Return the number of elapsed seconds of the wall clock time, user time and system time as a formatted string.

Private Attributes
Timer	timer_

std::string	format_

std::variant< std::ostream *, std::pair< std::shared_ptr< spdlog::logger >, spdlog::level::level_enum > >	output_

Detailed Description

Measures execution time between construction and destruction. AutoTimer can output either to a std::ostream or to a spdlog::logger

This class is very useful when you want to measure the execution time of a particular piece of code:

  lf::io::GmshReader reader(
      std::make_unique<lf::mesh::hybrid2d::MeshFactory>(2), "mesh.msh");
 
  // We want to measure how long it takes to assemble a mass matrix on this
  // mesh:
  auto fes =
      std::make_shared<lf::uscalfe::FeSpaceLagrangeO1<double>>(reader.mesh());
  lf::uscalfe::ReactionDiffusionElementMatrixProvider emp(
      fes, lf::mesh::utils::MeshFunctionConstant(1.0),
      lf::mesh::utils::MeshFunctionConstant(0.0));
  lf::assemble::COOMatrix<double> sm(fes->LocGlobMap().NumDofs(),
                                     fes->LocGlobMap().NumDofs());
  {
    std::cout << "Start assembly" << std::endl;
 
    // start measuring the runtime from here:
    lf::base::AutoTimer at;
    lf::assemble::AssembleMatrixLocally(0, fes->LocGlobMap(), fes->LocGlobMap(),
                                        emp, sm);
  }  // upon destruction of the AutoTimer `at`, the measured runtime will be
     // reported to std::cout.

See also: Timer

Definition at line 182 of file timer.h.

Constructor & Destructor Documentation

◆ AutoTimer() [1/5]

lf::base::AutoTimer::AutoTimer ( std::string format = Timer::kDefaultFormat )

explicit

Create a new AutoTimer that will report time measurements to std::cout when destructed.

Parameters

format Optional format string that specifies how the measured execution time is printed. See Timer::Format().

Definition at line 142 of file timer.cc.

◆ AutoTimer() [2/5]

lf::base::AutoTimer::AutoTimer	(	std::ostream &	stream,
		std::string	format = Timer::kDefaultFormat )

explicit

Create a new AutoTimer that will report to the given stream during destruction.

Parameters

stream	The stream to which output should be written.
format	Optional format string that specifies how the measured execution time is printed. See Timer::Format().

Definition at line 145 of file timer.cc.

◆ AutoTimer() [3/5]

lf::base::AutoTimer::AutoTimer	(	std::shared_ptr< spdlog::logger >	logger,
		spdlog::level::level_enum	level = spdlog::level::level_enum::info,
		std::string	format = Timer::kDefaultFormat )

explicit

Create a new AutoTimer that will report to the given spdlog::logger on destruction.

Parameters

logger	The spdlog logger object to which the timer should write. See Loggers and Debug output .
level	The logging level at which the message will be logged.
format	Optional format string that specifies how the measured execution time is printed. See Timer::Format().

Definition at line 148 of file timer.cc.

◆ AutoTimer() [4/5]

lf::base::AutoTimer::AutoTimer ( const AutoTimer & )

default

◆ AutoTimer() [5/5]

lf::base::AutoTimer::AutoTimer ( AutoTimer && )

default

◆ ~AutoTimer()

lf::base::AutoTimer::~AutoTimer ( )

Destructor of AutoTimer, calls Report().

Definition at line 153 of file timer.cc.

References lf::base::Timer::IsStopped(), Report(), lf::base::Timer::Stop(), and timer_.

Member Function Documentation

◆ Elapsed()

Timer::cpu_times lf::base::AutoTimer::Elapsed ( ) const

noexcept

Retrieve the elapsed time since the construction.

See also: Timer::Elapsed()

Definition at line 186 of file timer.cc.

References lf::base::Timer::Elapsed(), and timer_.

◆ Format()

std::string lf::base::AutoTimer::Format ( std::string_view format = Timer::kDefaultFormat ) const

Return the number of elapsed seconds of the wall clock time, user time and system time as a formatted string.

Parameters

format The fmt format string that is used to format the output. See below for possible fmt arguments.

Returns: The formatted string

format named arguments:

The following named arguments can appear in the format parameter:

name	replacement value
`w`	`Elapsed().wall`
`u`	`Elapsed().user`
`s`	`Elapsed().system`
`t`	`Elapsed().user + Elapsed().system`
`p`	`(Elapsed().user + Elapsed().system)/Elapsed().wall*100.`

Definition at line 190 of file timer.cc.

References lf::base::Timer::Format(), and timer_.

◆ FormatString()

const std::string & lf::base::AutoTimer::FormatString ( ) const

Retrieve the format string that was passed in the constructor.

Definition at line 175 of file timer.cc.

References format_.

◆ logger()

const std::shared_ptr< spdlog::logger > & lf::base::AutoTimer::logger ( ) const

Retrieve the logger that was passed in the constructor.

Exceptions

std::bad_variant_access if a std::ostream was passed in the constructor.

Definition at line 169 of file timer.cc.

References output_.

◆ operator=() [1/2]

AutoTimer & lf::base::AutoTimer::operator= ( AutoTimer && )

default

◆ operator=() [2/2]

AutoTimer & lf::base::AutoTimer::operator= ( const AutoTimer & )

default

◆ ostream()

std::ostream & lf::base::AutoTimer::ostream ( ) const

Retrieve the output stream object that was passed in the constructor.

Exceptions

std::bad_variant_access if a spdlog::logger was passed in the constructor.

Definition at line 165 of file timer.cc.

References output_.

Referenced by Report().

◆ Report()

void lf::base::AutoTimer::Report ( )

Report time (wall, user, system) since construction of AutoTimer() to either a std::ostream or spdlog::logger that was passed in the constructor.

Note: When the output is written to a std::ostream, this method will insert an additional newline character at the end.

Definition at line 177 of file timer.cc.

References lf::base::Timer::Format(), format_, ostream(), output_, and timer_.

Referenced by ~AutoTimer().

Member Data Documentation

◆ format_

std::string lf::base::AutoTimer::format_

private

Definition at line 268 of file timer.h.

Referenced by FormatString(), and Report().

◆ output_

std::variant<std::ostream*, std::pair<std::shared_ptr<spdlog::logger>, spdlog::level::level_enum> > lf::base::AutoTimer::output_

private

Definition at line 273 of file timer.h.

Referenced by logger(), ostream(), and Report().

◆ timer_

Timer lf::base::AutoTimer::timer_

private

Definition at line 267 of file timer.h.

Referenced by Elapsed(), Format(), Report(), and ~AutoTimer().

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

/__w/lehrfempp/lehrfempp/lib/lf/base/timer.h
/__w/lehrfempp/lehrfempp/lib/lf/base/timer.cc

Public Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

◆ AutoTimer() [1/5]

◆ AutoTimer() [2/5]

◆ AutoTimer() [3/5]

◆ AutoTimer() [4/5]

◆ AutoTimer() [5/5]

◆ ~AutoTimer()

Member Function Documentation

◆ Elapsed()

◆ Format()

format named arguments:

◆ FormatString()

◆ logger()

◆ operator=() [1/2]

◆ operator=() [2/2]

◆ ostream()

◆ Report()

Member Data Documentation

◆ format_

◆ output_

◆ timer_