join::BasicStats< ClockPolicy > Class Template Reference

lock-free, multi-producer-safe performance statistics collector. More...

#include <statistics.hpp>

Public Types
using	Duration = typename ClockPolicy::Duration
using	TimePoint = typename ClockPolicy::TimePoint

Public Member Functions
	BasicStats (const std::string &name={})
	create instance.
	BasicStats (const BasicStats &other)=delete
	copy constructor.
BasicStats &	operator= (const BasicStats &other)=delete
	copy assignment.
	BasicStats (BasicStats &&other)=delete
	move constructor.
BasicStats &	operator= (BasicStats &&other)=delete
	move assignment.
	~BasicStats () noexcept
	destroy instance.
const std::string &	name () const noexcept
	get metric name.
TimePoint	start () const noexcept
	mark the beginning of a measured interval.
void	stop (TimePoint startTime) noexcept
	mark the end of a measured interval and update all aggregates.
void	reset () noexcept
	reset all accumulators to their initial state.
uint64_t	count () const noexcept
	total number of completed intervals.
Duration	last () const noexcept
	duration of the most recently completed interval.
Duration	min () const noexcept
	minimum duration observed across all completed intervals.
Duration	max () const noexcept
	maximum duration observed across all completed intervals.
std::chrono::duration< double, std::nano >	mean () const noexcept
	arithmetic mean of all completed intervals.
double	throughput () const noexcept
	operations per second.
Duration	percentile (double p) const noexcept
	compute the requested percentile from the HDR histogram.
int	mlock () const noexcept
	lock histogram memory in RAM.

Detailed Description

template<class ClockPolicy>
class join::BasicStats< ClockPolicy >

lock-free, multi-producer-safe performance statistics collector.

Member Typedef Documentation

Duration

template<class ClockPolicy >

using join::BasicStats< ClockPolicy >::Duration = typename ClockPolicy::Duration

TimePoint

template<class ClockPolicy >

using join::BasicStats< ClockPolicy >::TimePoint = typename ClockPolicy::TimePoint

Constructor & Destructor Documentation

BasicStats() [1/3]

template<class ClockPolicy >

join::BasicStats< ClockPolicy >::BasicStats ( const std::string & name = {} )

inlineexplicit

create instance.

Parameters

name	metric name.

Exceptions

std::runtime_error

if the clock is not invariant.

BasicStats() [2/3]

template<class ClockPolicy >

join::BasicStats< ClockPolicy >::BasicStats ( const BasicStats< ClockPolicy > & other )

delete

copy constructor.

Parameters

other

other object to copy.

BasicStats() [3/3]

template<class ClockPolicy >

join::BasicStats< ClockPolicy >::BasicStats ( BasicStats< ClockPolicy > && other )

delete

move constructor.

Parameters

other

other object to move.

~BasicStats()

template<class ClockPolicy >

join::BasicStats< ClockPolicy >::~BasicStats ( )

inlinenoexcept

destroy instance.

Member Function Documentation

count()

template<class ClockPolicy >

uint64_t join::BasicStats< ClockPolicy >::count ( ) const

inlinenoexcept

total number of completed intervals.

Returns

sample count.

last()

template<class ClockPolicy >

Duration join::BasicStats< ClockPolicy >::last ( ) const

inlinenoexcept

duration of the most recently completed interval.

Returns

last measured duration.

max()

template<class ClockPolicy >

Duration join::BasicStats< ClockPolicy >::max ( ) const

inlinenoexcept

maximum duration observed across all completed intervals.

Returns

maximum measured duration, or zero if no interval has been recorded.

mean()

template<class ClockPolicy >

std::chrono::duration< double, std::nano > join::BasicStats< ClockPolicy >::mean ( ) const

inlinenoexcept

arithmetic mean of all completed intervals.

Returns

mean measured duration, or zero if no interval has been recorded.

min()

template<class ClockPolicy >

Duration join::BasicStats< ClockPolicy >::min ( ) const

inlinenoexcept

minimum duration observed across all completed intervals.

Returns

minimum measured duration, or zero if no interval has been recorded.

mlock()

template<class ClockPolicy >

int join::BasicStats< ClockPolicy >::mlock ( ) const

inlinenoexcept

lock histogram memory in RAM.

Returns

0 on success, -1 on failure.

name()

template<class ClockPolicy >

const std::string & join::BasicStats< ClockPolicy >::name ( ) const

inlinenoexcept

get metric name.

Returns

metric name.

operator=() [1/2]

template<class ClockPolicy >

BasicStats & join::BasicStats< ClockPolicy >::operator= ( BasicStats< ClockPolicy > && other )

delete

move assignment.

Parameters

other

other object to move.

Returns

a reference to the current object.

operator=() [2/2]

template<class ClockPolicy >

BasicStats & join::BasicStats< ClockPolicy >::operator= ( const BasicStats< ClockPolicy > & other )

delete

copy assignment.

Parameters

other

other object to copy.

Returns

a reference to the current object.

percentile()

template<class ClockPolicy >

Duration join::BasicStats< ClockPolicy >::percentile ( double p ) const

inlinenoexcept

compute the requested percentile from the HDR histogram.

Parameters

p	percentile in [0.0, 100.0].

Returns

latency at the p-th percentile; zero if no samples have been recorded.

reset()

template<class ClockPolicy >

void join::BasicStats< ClockPolicy >::reset ( )

inlinenoexcept

reset all accumulators to their initial state.

start()

template<class ClockPolicy >

TimePoint join::BasicStats< ClockPolicy >::start ( ) const

inlinenoexcept

mark the beginning of a measured interval.

Returns

time point to be passed to the matching stop() call.

stop()

template<class ClockPolicy >

void join::BasicStats< ClockPolicy >::stop ( TimePoint startTime )

inlinenoexcept

mark the end of a measured interval and update all aggregates.

Parameters

startTime

time point returned by the matching start() call.

throughput()

template<class ClockPolicy >

double join::BasicStats< ClockPolicy >::throughput ( ) const

inlinenoexcept

operations per second.

Returns

throughput in ops/s.

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

• core/include/join/clock.hpp
• core/include/join/statistics.hpp