wangle::ConnectionManager::DrainHelper Class Reference

Inheritance diagram for wangle::ConnectionManager::DrainHelper:

Public Member Functions
	DrainHelper (ConnectionManager &manager)
ShutdownState	getShutdownState ()
void	setShutdownState (ShutdownState state)
void	startDrainPartial (double pct, std::chrono::milliseconds idleGrace)
void	startDrainAll (std::chrono::milliseconds idleGrace)
void	runLoopCallback () noexceptoverride
void	timeoutExpired () noexceptoverride
void	drainConnections ()
void	idleGracefulTimeoutExpired ()
void	startDrain (std::chrono::milliseconds idleGrace)
ConnectionIterator	drainStartIterator () const
Public Member Functions inherited from folly::EventBase::LoopCallback
virtual	~LoopCallback ()=default
void	cancelLoopCallback ()
bool	isLoopCallbackScheduled () const
Public Member Functions inherited from folly::AsyncTimeout
	AsyncTimeout (TimeoutManager *timeoutManager)
	AsyncTimeout (EventBase *eventBase)
	AsyncTimeout (TimeoutManager *timeoutManager, InternalEnum internal)
	AsyncTimeout (EventBase *eventBase, InternalEnum internal)
	AsyncTimeout ()
virtual	~AsyncTimeout ()
bool	scheduleTimeout (uint32_t milliseconds)
bool	scheduleTimeout (TimeoutManager::timeout_type timeout)
void	cancelTimeout ()
bool	isScheduled () const
void	attachTimeoutManager (TimeoutManager *timeoutManager, InternalEnum internal=InternalEnum::NORMAL)
void	attachEventBase (EventBase *eventBase, InternalEnum internal=InternalEnum::NORMAL)
void	detachTimeoutManager ()
void	detachEventBase ()
const TimeoutManager *	getTimeoutManager ()
struct event *	getEvent ()

Private Attributes
bool	all_ {true}
double	pct_ {1.0}
ConnectionManager &	manager_
ShutdownState	shutdownState_ {ShutdownState::NONE}

Additional Inherited Members
Public Types inherited from folly::AsyncTimeout
typedef TimeoutManager::InternalEnum	InternalEnum
Static Public Member Functions inherited from folly::AsyncTimeout
template<typename TCallback >
static std::unique_ptr< AsyncTimeout >	make (TimeoutManager &manager, TCallback &&callback)
template<typename TCallback >
static std::unique_ptr< AsyncTimeout >	schedule (TimeoutManager::timeout_type timeout, TimeoutManager &manager, TCallback &&callback)

Detailed Description

Definition at line 186 of file ConnectionManager.h.

Constructor & Destructor Documentation

wangle::ConnectionManager::DrainHelper::DrainHelper ( ConnectionManager &  manager )

inlineexplicit

Definition at line 190 of file ConnectionManager.h.

        : folly::AsyncTimeout(manager.eventBase_),
          manager_(manager) {}

Member Function Documentation

void wangle::ConnectionManager::DrainHelper::drainConnections

(

)

Definition at line 184 of file ConnectionManager.cpp.

References wangle::ManagedConnection::fireCloseWhenIdle(), wangle::ManagedConnection::fireNotifyPendingShutdown(), g(), and wangle::ManagedConnection::isBusy().

                                               {
  DestructorGuard g(&manager_);
  size_t numCleared = 0;
  size_t numKept = 0;

  auto it = manager_.drainIterator_;

  CHECK(shutdownState_ == ShutdownState::NOTIFY_PENDING_SHUTDOWN ||
        shutdownState_ == ShutdownState::CLOSE_WHEN_IDLE);
  while (it != manager_.conns_.end() && (numKept + numCleared) < 64) {
    ManagedConnection& conn = *it++;
    if (shutdownState_ == ShutdownState::NOTIFY_PENDING_SHUTDOWN) {
      conn.fireNotifyPendingShutdown();
      numKept++;
    } else { // CLOSE_WHEN_IDLE
      // Second time around: close idle sessions. If they aren't idle yet,
      // have them close when they are idle
      if (conn.isBusy()) {
        numKept++;
      } else {
        numCleared++;
      }
      conn.fireCloseWhenIdle(!manager_.notifyPendingShutdown_);
    }
  }

  if (shutdownState_ == ShutdownState::CLOSE_WHEN_IDLE) {
    VLOG(2) << "Idle connections cleared: " << numCleared <<
      ", busy conns kept: " << numKept;
  } else {
    VLOG(3) << this << " notified n=" << numKept;
  }
  manager_.drainIterator_ = it;
  if (it != manager_.conns_.end()) {
    manager_.eventBase_->runInLoop(this);
  } else {
    if (shutdownState_ == ShutdownState::NOTIFY_PENDING_SHUTDOWN) {
      VLOG(3) << this << " finished notify_pending_shutdown";
      shutdownState_ = ShutdownState::NOTIFY_PENDING_SHUTDOWN_COMPLETE;
      if (!isScheduled()) {
        // The idle grace timer already fired, start over immediately
        shutdownState_ = ShutdownState::CLOSE_WHEN_IDLE;
        manager_.drainIterator_ = drainStartIterator();
        manager_.eventBase_->runInLoop(this);
      }
    } else {
      shutdownState_ = ShutdownState::CLOSE_WHEN_IDLE_COMPLETE;
    }
  }
}

ConnectionIterator wangle::ConnectionManager::DrainHelper::drainStartIterator ( ) const

inline

Definition at line 225 of file ConnectionManager.h.

                                                  {
      if (all_) {
        return manager_.conns_.begin();
      }
      auto it = manager_.conns_.begin();
      const auto conns_size = manager_.conns_.size();
      const auto numToDrain =
        std::max<size_t>(0, std::min<size_t>(conns_size, conns_size * pct_));
      std::advance(it, conns_size - numToDrain);
      return it;
    }

ShutdownState wangle::ConnectionManager::DrainHelper::getShutdownState ( )

inline

Definition at line 194 of file ConnectionManager.h.

References wangle::ConnectionManager::NONE.

                                     {
      // only cares about full shutdown state
      if (!all_) {
        return ShutdownState::NONE;
      }
      return shutdownState_;
    }

void wangle::ConnectionManager::DrainHelper::idleGracefulTimeoutExpired

(

)

Definition at line 236 of file ConnectionManager.cpp.

                                                         {
  VLOG(2) << this << " idleGracefulTimeoutExpired";
  if (shutdownState_ ==
      ShutdownState::NOTIFY_PENDING_SHUTDOWN_COMPLETE) {
    shutdownState_ = ShutdownState::CLOSE_WHEN_IDLE;
    manager_.drainIterator_ = drainStartIterator();
    drainConnections();
  } else {
    VLOG(4) << this << " idleGracefulTimeoutExpired during "
      "NOTIFY_PENDING_SHUTDOWN, ignoring";
  }
}

void wangle::ConnectionManager::DrainHelper::runLoopCallback ( )

inlineoverridevirtualnoexcept

Implements folly::EventBase::LoopCallback.

Definition at line 209 of file ConnectionManager.h.

References wangle::ConnectionManager::drainConnections().

                                             {
      VLOG(3) << "Draining more conns from loop callback";
      drainConnections();
    }

void wangle::ConnectionManager::DrainHelper::setShutdownState ( ShutdownState  state )

inline

Definition at line 202 of file ConnectionManager.h.

                                               {
      shutdownState_ = state;
    }

void wangle::ConnectionManager::DrainHelper::startDrain

(

std::chrono::milliseconds

idleGrace

)

Definition at line 168 of file ConnectionManager.cpp.

                                   {
  if (idleGrace.count() > 0) {
    shutdownState_ = ShutdownState::NOTIFY_PENDING_SHUTDOWN;
    scheduleTimeout(idleGrace);
    VLOG(3) << "Scheduling idle grace period of " << idleGrace.count() << "ms";
  } else {
    manager_.notifyPendingShutdown_ = false;
    shutdownState_ = ShutdownState::CLOSE_WHEN_IDLE;
    VLOG(3) << "proceeding directly to closing idle connections";
  }
  manager_.drainIterator_ = drainStartIterator();
  drainConnections();
}

void wangle::ConnectionManager::DrainHelper::startDrainAll

(

std::chrono::milliseconds

idleGrace

)

Definition at line 157 of file ConnectionManager.cpp.

                                   {
  all_ = true;
  pct_ = 1.0;
  if (isScheduled()) {
    // if we are in the middle of a partial, abort and convert to all
    cancelTimeout();
  }
  startDrain(idleGrace);
}

void wangle::ConnectionManager::DrainHelper::startDrainPartial	(	double	pct,
		std::chrono::milliseconds	idleGrace
	)

Definition at line 150 of file ConnectionManager.cpp.

                                               {
  all_ = false;
  pct_ = pct;
  startDrain(idleGrace);
}

void wangle::ConnectionManager::DrainHelper::timeoutExpired ( )

inlineoverridevirtualnoexcept

timeoutExpired() is invoked when the timeout period has expired.

Implements folly::AsyncTimeout.

Definition at line 214 of file ConnectionManager.h.

References wangle::ConnectionManager::drainConnections(), and wangle::ConnectionManager::idleGracefulTimeoutExpired().

                                            {
      VLOG(3) << "Idle grace expired";
      idleGracefulTimeoutExpired();
    }

Member Data Documentation

bool wangle::ConnectionManager::DrainHelper::all_ {true}

private

Definition at line 238 of file ConnectionManager.h.

ConnectionManager& wangle::ConnectionManager::DrainHelper::manager_

private

Definition at line 240 of file ConnectionManager.h.

double wangle::ConnectionManager::DrainHelper::pct_ {1.0}

private

Definition at line 239 of file ConnectionManager.h.

ShutdownState wangle::ConnectionManager::DrainHelper::shutdownState_ {ShutdownState::NONE}

private

Definition at line 241 of file ConnectionManager.h.

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

• proxygen/wangle/wangle/acceptor/ConnectionManager.h
• proxygen/wangle/wangle/acceptor/ConnectionManager.cpp