lf::base::AutoTimer Class Reference

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.

References format_, and output_.

Referenced by AutoTimer(), AutoTimer(), operator=(), and operator=().

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.

References format_, and output_.

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.

References format_, logger(), and output_.

AutoTimer() [4/5]

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

default

References AutoTimer().

AutoTimer() [5/5]

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

default

References AutoTimer().

~AutoTimer()

lf::base::AutoTimer::~AutoTimer

(

)

Destructor of AutoTimer, calls Report().

Definition at line 153 of file timer.cc.

References Report(), and timer_.

Member Function Documentation

Elapsed()

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

nodiscardnoexcept

Retrieve the elapsed time since the construction.

See also

Timer::Elapsed()

Definition at line 186 of file timer.cc.

References timer_.

Format()

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

nodiscard

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 timer_.

Referenced by operator=().

FormatString()

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

nodiscard

Retrieve the format string that was passed in the constructor.

Definition at line 175 of file timer.cc.

References format_.

Referenced by operator=().

logger()

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

nodiscard

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_.

Referenced by AutoTimer(), and operator=().

operator=() [1/2]

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

default

References AutoTimer(), Format(), FormatString(), logger(), ostream(), and Report().

operator=() [2/2]

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

default

References AutoTimer().

ostream()

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

nodiscard

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 operator=(), and 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 format_, ostream(), output_, and timer_.

Referenced by operator=(), and ~AutoTimer().

Member Data Documentation

format_

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

private

Definition at line 268 of file timer.h.

Referenced by AutoTimer(), AutoTimer(), AutoTimer(), 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 AutoTimer(), AutoTimer(), AutoTimer(), 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().

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

• /home/runner/work/lehrfempp/lehrfempp/lib/lf/base/timer.h
• /home/runner/work/lehrfempp/lehrfempp/lib/lf/base/timer.cc