folly::detail::BufferedStat< DigestT, ClockT > Class Template Reference

#include <BufferedStat.h>

Inheritance diagram for folly::detail::BufferedStat< DigestT, ClockT >:

Classes
struct	TimePointHolder

Public Types
using	TimePoint = typename ClockT::time_point

Public Member Functions
	BufferedStat ()=delete
	BufferedStat (typename ClockT::duration bufferDuration, size_t bufferSize, size_t digestSize)
virtual	~BufferedStat ()
void	append (double value, TimePoint now=ClockT::now())
void	flush ()

Protected Member Functions
virtual void	onNewDigest (DigestT digest, TimePoint newExpiry, TimePoint oldExpiry, const std::unique_lock< SharedMutex > &g)=0
std::unique_lock< SharedMutex >	updateIfExpired (TimePoint now)
std::unique_lock< SharedMutex >	update ()

Protected Attributes
const ClockT::duration	bufferDuration_
std::atomic< TimePointHolder >	expiry_
SharedMutex	mutex_

Private Types
enum	UpdateMode { UpdateMode::OnExpiry, UpdateMode::Now }

Private Member Functions
void	doUpdate (TimePoint now, const std::unique_lock< SharedMutex > &g, UpdateMode updateMode)
TimePoint	roundUp (TimePoint t)

Private Attributes
DigestBuilder< DigestT >	digestBuilder_

Detailed Description

template<typename DigestT, typename ClockT>
class folly::detail::BufferedStat< DigestT, ClockT >

Definition at line 32 of file BufferedStat.h.

Member Typedef Documentation

template<typename DigestT, typename ClockT>

using folly::detail::BufferedStat< DigestT, ClockT >::TimePoint = typename ClockT::time_point

Definition at line 34 of file BufferedStat.h.

Member Enumeration Documentation

template<typename DigestT, typename ClockT>

enum folly::detail::BufferedStat::UpdateMode

strongprivate

Enumerator
OnExpiry
Now

Definition at line 81 of file BufferedStat.h.

                        {
    OnExpiry,
    Now,
  };

Constructor & Destructor Documentation

template<typename DigestT, typename ClockT>

folly::detail::BufferedStat< DigestT, ClockT >::BufferedStat ( )

delete

template<typename DigestT , typename ClockT>

folly::detail::BufferedStat< DigestT, ClockT >::BufferedStat	(	typename ClockT::duration	bufferDuration,
		size_t	bufferSize,
		size_t	digestSize
	)

Definition at line 28 of file BufferedStat-defs.h.

References folly::detail::BufferedStat< DigestT, ClockT >::expiry_, now(), and folly::detail::BufferedStat< DigestT, ClockT >::roundUp().

    : bufferDuration_(bufferDuration), digestBuilder_(bufferSize, digestSize) {
  expiry_.store(
      TimePointHolder(roundUp(ClockT::now())), std::memory_order_relaxed);
}

template<typename DigestT, typename ClockT>

virtual folly::detail::BufferedStat< DigestT, ClockT >::~BufferedStat ( )

inlinevirtual

Definition at line 43 of file BufferedStat.h.

{}

Member Function Documentation

template<typename DigestT , typename ClockT >

void folly::detail::BufferedStat< DigestT, ClockT >::append	(	double	value,
		TimePoint	now = ClockT::now()
	)

Definition at line 38 of file BufferedStat-defs.h.

References folly::detail::BufferedStat< DigestT, ClockT >::digestBuilder_, folly::detail::BufferedStat< DigestT, ClockT >::doUpdate(), folly::detail::BufferedStat< DigestT, ClockT >::expiry_, g(), folly::detail::BufferedStat< DigestT, ClockT >::mutex_, folly::detail::BufferedStat< DigestT, ClockT >::OnExpiry, and UNLIKELY.

Referenced by folly::detail::BufferedStat< folly::TDigest, ClockT >::~BufferedStat().

                                                                      {
  if (UNLIKELY(now > expiry_.load(std::memory_order_relaxed).tp)) {
    std::unique_lock<SharedMutex> g(mutex_, std::try_to_lock_t());
    if (g.owns_lock()) {
      doUpdate(now, g, UpdateMode::OnExpiry);
    }
  }
  digestBuilder_.append(value);
}

template<typename DigestT , typename ClockT >

void folly::detail::BufferedStat< DigestT, ClockT >::doUpdate ( TimePoint  now, const std::unique_lock< SharedMutex > &  g, UpdateMode  updateMode  )

private

Definition at line 73 of file BufferedStat-defs.h.

References folly::detail::BufferedStat< DigestT, ClockT >::digestBuilder_, folly::detail::BufferedStat< DigestT, ClockT >::expiry_, g(), now(), folly::detail::BufferedStat< DigestT, ClockT >::Now, folly::detail::BufferedStat< DigestT, ClockT >::onNewDigest(), and folly::detail::BufferedStat< DigestT, ClockT >::roundUp().

Referenced by folly::detail::BufferedStat< DigestT, ClockT >::append(), folly::detail::BufferedStat< DigestT, ClockT >::flush(), and folly::detail::BufferedStat< DigestT, ClockT >::updateIfExpired().

                           {
  DCHECK(g.owns_lock());
  // Check that no other thread has performed the slide after the check
  auto oldExpiry = expiry_.load(std::memory_order_relaxed).tp;
  if (now > oldExpiry || updateMode == UpdateMode::Now) {
    now = roundUp(now);
    expiry_.store(TimePointHolder(now), std::memory_order_relaxed);
    onNewDigest(digestBuilder_.build(), now, oldExpiry, g);
  }
}

template<typename DigestT , typename ClockT >

void folly::detail::BufferedStat< DigestT, ClockT >::flush

(

)

Definition at line 67 of file BufferedStat-defs.h.

References folly::detail::BufferedStat< DigestT, ClockT >::doUpdate(), g(), folly::detail::BufferedStat< DigestT, ClockT >::mutex_, now(), and folly::detail::BufferedStat< DigestT, ClockT >::Now.

Referenced by folly::detail::BufferedStat< folly::TDigest, ClockT >::~BufferedStat().

                                          {
  std::unique_lock<SharedMutex> g(mutex_);
  doUpdate(ClockT::now(), g, UpdateMode::Now);
}

template<typename DigestT, typename ClockT>

virtual void folly::detail::BufferedStat< DigestT, ClockT >::onNewDigest ( DigestT  digest, TimePoint  newExpiry, TimePoint  oldExpiry, const std::unique_lock< SharedMutex > &  g  )

protectedpure virtual

Implemented in folly::detail::BufferedSlidingWindow< DigestT, ClockT >, folly::detail::BufferedSlidingWindow< folly::TDigest, ClockT >, folly::detail::BufferedDigest< DigestT, ClockT >, and folly::detail::BufferedDigest< folly::TDigest, ClockT >.

Referenced by folly::detail::BufferedStat< DigestT, ClockT >::doUpdate().

template<typename DigestT , typename ClockT >

BufferedStat< DigestT, ClockT >::TimePoint folly::detail::BufferedStat< DigestT, ClockT >::roundUp ( TimePoint  t )

private

Definition at line 50 of file BufferedStat-defs.h.

References folly::detail::BufferedStat< DigestT, ClockT >::bufferDuration_, and folly::pushmi::detail::t.

Referenced by folly::detail::BufferedStat< DigestT, ClockT >::BufferedStat(), and folly::detail::BufferedStat< DigestT, ClockT >::doUpdate().

                                                  {
  auto remainder = t.time_since_epoch() % bufferDuration_;
  if (remainder.count() != 0) {
    return t + bufferDuration_ - remainder;
  }
  return t;
}

template<typename DigestT, typename ClockT>

std::unique_lock<SharedMutex> folly::detail::BufferedStat< DigestT, ClockT >::update ( )

protected

template<typename DigestT , typename ClockT >

std::unique_lock< SharedMutex > folly::detail::BufferedStat< DigestT, ClockT >::updateIfExpired ( TimePoint  now )

protected

Definition at line 59 of file BufferedStat-defs.h.

References folly::detail::BufferedStat< DigestT, ClockT >::doUpdate(), g(), folly::detail::BufferedStat< DigestT, ClockT >::mutex_, and folly::detail::BufferedStat< DigestT, ClockT >::OnExpiry.

Referenced by folly::detail::BufferedDigest< DigestT, ClockT >::get(), and folly::detail::BufferedSlidingWindow< DigestT, ClockT >::get().

                   {
  std::unique_lock<SharedMutex> g(mutex_);
  doUpdate(now, g, UpdateMode::OnExpiry);
  return g;
}

Member Data Documentation

template<typename DigestT, typename ClockT>

const ClockT::duration folly::detail::BufferedStat< DigestT, ClockT >::bufferDuration_

protected

Definition at line 61 of file BufferedStat.h.

Referenced by folly::detail::BufferedSlidingWindow< DigestT, ClockT >::onNewDigest(), and folly::detail::BufferedStat< DigestT, ClockT >::roundUp().

template<typename DigestT, typename ClockT>

DigestBuilder<DigestT> folly::detail::BufferedStat< DigestT, ClockT >::digestBuilder_

private

Definition at line 78 of file BufferedStat.h.

Referenced by folly::detail::BufferedStat< DigestT, ClockT >::append(), and folly::detail::BufferedStat< DigestT, ClockT >::doUpdate().

template<typename DigestT, typename ClockT>

std::atomic<TimePointHolder> folly::detail::BufferedStat< DigestT, ClockT >::expiry_

protected

Definition at line 62 of file BufferedStat.h.

Referenced by folly::detail::BufferedStat< DigestT, ClockT >::append(), folly::detail::BufferedStat< DigestT, ClockT >::BufferedStat(), and folly::detail::BufferedStat< DigestT, ClockT >::doUpdate().

template<typename DigestT, typename ClockT>

SharedMutex folly::detail::BufferedStat< DigestT, ClockT >::mutex_

protected

Definition at line 63 of file BufferedStat.h.

Referenced by folly::detail::BufferedStat< DigestT, ClockT >::append(), folly::detail::BufferedStat< DigestT, ClockT >::flush(), and folly::detail::BufferedStat< DigestT, ClockT >::updateIfExpired().

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

• proxygen/folly/folly/stats/detail/BufferedStat.h
• proxygen/folly/folly/stats/detail/BufferedStat-defs.h