#include <LoadBalance.hpp>

Inheritance diagram for freedm::broker::lb::LBAgent:

Public Member Functions
	LBAgent ()

int	Run ()

Protected Member Functions
CPeerNode	GetMe ()
	Gets a CPeerNode representing this process. More...

std::string	GetUUID () const
	Gets the UUID of this process. More...

Private Types
enum	State { SUPPLY, DEMAND, NORMAL }

Private Member Functions
void	DraftStandard (const boost::system::error_code &error)
	The code that runs after the draft request replies have arrived. More...

void	FirstRound (const boost::system::error_code &error)
	The code that runs the firtst round of the LB phase. More...

void	HandleCollectedState (const sc::CollectedStateMessage &m)
	Handles the collected state coming from state collection. More...

void	HandleCollectedState (const CollectedStateMessage &m)
	Handles the collected state coming from load balancing. More...

void	HandleDraftAccept (const DraftAcceptMessage &m, CPeerNode peer)
	Handles the draft accept message coming from the demand node. More...

void	HandleDraftAge (const DraftAgeMessage &m, CPeerNode peer)
	Handles the draft age message coming from the demand node. More...

void	HandleDraftRequest (const DraftRequestMessage &m, CPeerNode peer)
	Handles the draft request originating from the supply node. More...

void	HandleDraftSelect (const DraftSelectMessage &m, CPeerNode peer)
	Handles the draft select message coming from the supply node. More...

void	HandleIncomingMessage (boost::shared_ptr< const ModuleMessage > m, CPeerNode peer)
	First handler for an incoming message. More...

void	HandlePeerList (const gm::PeerListMessage &m, CPeerNode peer)
	Handles the peerlist coming from the group leader. More...

void	HandleStateChange (const StateChangeMessage &m, CPeerNode peer)
	Handles a node announcing its state change. More...

void	HandleTooLate (const TooLateMessage &m)
	Handles the draft reject message coming from the demand node. More...

bool	InvariantCheck ()
	Check the invariant prior to starting a new migration. More...

void	LoadManage (const boost::system::error_code &error)
	The code that the supply nodes use to start doing migrations. More...

void	LoadTable ()
	Displays the load table to show DGI state. More...

ModuleMessage	MessageCollectedState (float state)

ModuleMessage	MessageDraftAccept (float amount)
	Generates the message that the demand node uses to confirm the migration. More...

ModuleMessage	MessageDraftAge (float age)
	Generates message demand nodes send in response to DraftRequest. More...

ModuleMessage	MessageDraftRequest ()
	Generates message supply nodes send to demand nodes. More...

ModuleMessage	MessageDraftSelect (float amount)
	Generates the message that the supply node uses to select a demand node. More...

ModuleMessage	MessageStateChange (std::string state)
	Generates the message announcing current node state. More...

ModuleMessage	MessageStateCollection ()
	Generates the message used to request a state collection. More...

ModuleMessage	MessageTooLate (float amount)
	Generates the message sent by the demand node to refuse migration. More...

void	MoveToPeerSet (PeerSet &ps, CPeerNode peer)
	Moves a peer to the specified peerset. More...

ModuleMessage	PrepareForSending (const LoadBalancingMessage &m, std::string recipient="lb")
	Boilerplate for preparing a message. More...

void	ReadDevices ()
	Updates the state from the devices. More...

void	ScheduleNextRound ()
	Schedules the LoadManage that runs next round. More...

void	ScheduleStateCollection ()
	Sends the request to perform state collection. More...

void	SendDraftAccept (CPeerNode peer, float step)
	Sends draft accept to the specified peer. More...

void	SendDraftAge (CPeerNode peer)
	Sends draftage to the specified peer. More...

void	SendDraftRequest ()
	Sends Draft request to all the demand peers. More...

void	SendDraftSelect (CPeerNode peer, float step)
	Sends a draft select to the specified peer. More...

void	SendTooLate (CPeerNode peer, float step)
	Sends too late to the specified peer. More...

void	SendToPeerSet (const PeerSet &ps, const ModuleMessage &m)
	Sends a message to all peers in a peerset. More...

void	SetDESD (float desd)
	Sets DESD value to the specified level. More...

void	SetPStar (float pstar)
	Sets PStar to the specified level. More...

void	Synchronize (float k)
	Synchronizes the Fast-Style Loadbalance with the physical system. More...

void	UpdateState ()
	Updates the node's state. More...

Private Attributes
PeerSet	m_AllPeers
	All peers in group. More...

std::map< std::string, float >	m_DraftAge
	Pending migrations. More...

float	m_Gateway
	The gateway of this node. More...

PeerSet	m_InDemand
	Peers in the demand state. More...

PeerSet	m_InNormal
	Peers in the normal state. More...

PeerSet	m_InSupply
	Peers in the supply state. More...

std::string	m_Leader
	The coordinator of the group. More...

float	m_MigrationStep
	The amount to migrate. More...

float	m_NetGeneration
	The amount of generation created by attached devices. More...

float	m_PowerDifferential
	The powerflow used by the physical invariant. More...

float	m_PredictedGateway
	The gateway that we predict will be met by the devices. More...

CBroker::TimerHandle	m_RoundTimer
	Timer handle for the round timer. More...

State	m_State
	The current state of this peer. More...

bool	m_Synchronized
	If the system is synchronized with the physical system. More...

CBroker::TimerHandle	m_WaitTimer
	Timer handle for the request timer. More...

const boost::posix_time::time_duration	REQUEST_TIMEOUT
	The time it takes to get a draftrequest response. More...

const boost::posix_time::time_duration	ROUND_TIME
	The amount of time it takes to do an LB round. More...

Member Enumeration Documentation

enum freedm::broker::lb::LBAgent::State

private

Enumerator
SUPPLY
DEMAND
NORMAL

Constructor & Destructor Documentation

freedm::broker::lb::LBAgent::LBAgent ( )

LBAgent

Description:: : Constructor for the load balancing module

Precondition:: : Posix Main should register read handler and invoke this module

Postcondition:: : Object is initialized and ready to run load balancing

Limitations:: : None

Member Function Documentation

void freedm::broker::lb::LBAgent::DraftStandard ( const boost::system::error_code & error )

private

DraftStandard

Description:: This function is used to select the process(es) that the migration will happen with. The demand nodes send DraftAge messages indicating the amount of demand to fill.

Precondition:: DraftRequests were sent to the nodes whose replies will be processed

Postcondition:: DraftSelect messages are sent to the selected demand nodes.

void freedm::broker::lb::LBAgent::FirstRound ( const boost::system::error_code & error )

private

FirstRound

Description:: The code that is executed as part of the first loadbalance each round.

Precondition:: None

Postcondition:: if the timer wasn't cancelled this function requests state collection and calls the first load balance.

Parameters

error The reason this function was called.

CPeerNode IDGIModule::GetMe ( )

protectedinherited

GetMe

Description:: Gets a CPeerNode that refers to this process.

Returns: A CPeerNode referring to this process.

std::string IDGIModule::GetUUID ( ) const

protectedinherited

GetUUID

Description:: Gets this process's UUID.

Returns: This process's UUID

void freedm::broker::lb::LBAgent::HandleCollectedState ( const sc::CollectedStateMessage & m )

private

HandleCollectedState

Description:: State collection returns the collected state (via a message) this function handles that message and stores it into this node.

Precondition:: The message is valid

Postcondition:: The aggregate gateway, normal and demand member variables are set. Sends the normal to the members of the group.

Parameters

m	The message body that was recieved by this process.

Interaction Peers:: My state collection module, Members of my group.

Limitations:: Does not validate the source, integrity or contents of the message.

void freedm::broker::lb::LBAgent::HandleCollectedState ( const CollectedStateMessage & m )

private

HandleCollectedState

Description:: When the collected state arrives, the leader computes normal and pushes it out to all the peers. This method sets the normal value at this peer.

Precondition:: The message is valid

Postcondition:: This node is resynchronized.

Parameters

m	The message body that was recieved by this process.

Interaction Peers:: My leader.

Limitations:: Does not validate the source, integrity or contents of the message.

void freedm::broker::lb::LBAgent::HandleDraftAccept	(	const DraftAcceptMessage &	m,
		CPeerNode	peer
	)

private

HandleDraftAccept

Description:: An accept message will arrive from a demand node that has selected to accept a migration from this supply node.

Precondition:: m and peer is valid.

Postcondition:: If the node is in supply, it will adjust the gross powerflow to note the reciever has adjusted their power.

Parameters

m	The message body that was recieved by this process.
peer	The process that the message orginated from.

Interaction Peers:: A demand node in my group.

Limitations:: Does not validate the source, integrity or contents of the message.

void freedm::broker::lb::LBAgent::HandleDraftAge	(	const DraftAgeMessage &	m,
		CPeerNode	peer
	)

private

HandleDraftAge

Description:: A DraftAge message is sent by the demand node to a supply to indicate it is still in a demand state and would like to migrate. After the message is recieved this node will respond with drafting to instruct the demand node to commit a power change.

Precondition:: The message and peer are valid. This node should have sent a draft request message to peer previously.

Postcondition:: If in supply and the demand node is selected, a drafting message will be sent to the demand node.

Parameters

m	The message body that was recieved by this process.
peer	The process that the message orginated from.

Interaction Peers:: A demand node in the group.

Limitations:: Does not validate the source, integrity or contents of the message.

void freedm::broker::lb::LBAgent::HandleDraftRequest	(	const DraftRequestMessage &	m,
		CPeerNode	peer
	)

private

HandleDraftRequest

Description:: Handler for a DraftRequest message. A request message is sent by a supply node to see if a demand node wants to perform a migration.

Precondition:: The message is fully populated. The peer is valid.

Postcondition:: If this process is in the demand state, a DraftAge message is sent back to the orginating process.

Parameters

m	The message body that was recieved by this process.
peer	The process that the message orginated from.

Interaction Peers:: A group member who was in the supply state.

Limitations:: Does not validate the source, integrity or contents of the message.

void freedm::broker::lb::LBAgent::HandleDraftSelect	(	const DraftSelectMessage &	m,
		CPeerNode	peer
	)

private

HandleDraftSelect

Description:: A draft select message is accepted by a demand node as an indication a supply node is about to give it some tasty power. When the drafting message arrives the demand node will actuate it's physical leaves and signal the supply node to do the same by sending back an accept message.

Precondition:: There is a valid message pointer and peer passed into the module. All required ptree keys are present.

Postcondition:: If the node is in demand and will take the supply node's power this node will generate an accept message and change a device value to accept the new float.

Parameters

m	The message body that was recieved by this process.
peer	The process that the message orginated from.

Interaction Peers:: A supply node in my group.

Limitations:: Does not validate the source, integrity or contents of the message.

void freedm::broker::lb::LBAgent::HandleIncomingMessage	(	boost::shared_ptr< const ModuleMessage >	m,
		CPeerNode	peer
	)

privatevirtual

HandleIncomingMessage "Downcasts" incoming messages into a specific message type, and passes the message to an appropriate handler.

Precondition:: None

Postcondition:: The message is handled by the target handler or a warning is produced.

Parameters

m	the incoming message
peer	the node that sent this message (could be this DGI)

Implements freedm::broker::IDGIModule.

void freedm::broker::lb::LBAgent::HandlePeerList	(	const gm::PeerListMessage &	m,
		CPeerNode	peer
	)

private

HandlePeerList

Description:: Updates the list of peers this node is aware of.

Precondition:: There is a valid message pointer and peer passed into the module.

Postcondition:: The AllPeers, Normal, Supply, and Demand peersets are reset.

Parameters

m	The message body that was recieved by this process.
peer	The process that the message orginated from.

Interaction Peers:: Group leader.

Limitations:: Does not validate the source, integrity or contents of the message.

void freedm::broker::lb::LBAgent::HandleStateChange	(	const StateChangeMessage &	m,
		CPeerNode	peer
	)

private

HandleStateChange

Description:: Handles a peer announcing it is in a new state

Precondition:: The state message is fully populated. The peer is valid.

Postcondition:: The peer is removed from any state sets it is currently in and placed in a set by the contents of the message.

Parameters

m	The message body that was recieved by this process.
peer	The process that the message orginated from.

Interaction Peers:: A Group member.

Limitations:: Does not validate the source, integrity or contents of the message.

void freedm::broker::lb::LBAgent::HandleTooLate ( const TooLateMessage & m )

private

HandleTooLate

Description:: An accept message will arrive from a demand node that has selected to accept a migration from this supply node, but no longer needs that power.

Precondition:: m and peer is valid.

Postcondition:: This node will adjust its gross powerflow and revert the power setting to cancel the migration.

Parameters

m	The message body that was recieved by this process.

Interaction Peers:: A demand node in my group.

Limitations:: Does not validate the source, integrity or contents of the message.

bool freedm::broker::lb::LBAgent::InvariantCheck ( )

private

InvariantCheck

Description:: Evaluates the current truth of the physical invariant

Precondition:: none

Postcondition:: calculate the physical invariant using the Omega device

Returns: the truth value of the physical invariant

void freedm::broker::lb::LBAgent::LoadManage ( const boost::system::error_code & error )

private

LoadManage

Description:: : Manages the execution of the load balancing algorithm by broadcasting load changes and initiating SendDraftRequest() if in Supply

Precondition:: : Node is not in Fail state

Postcondition:: : Load state change is monitored, specific load changes are advertised to peers and restarts on timeout

Interaction Peers:: All peers in case of Demand state and transition to Normal from Demand;

Limitations:

void freedm::broker::lb::LBAgent::LoadTable ( )

private

LoadTable

Description:: Prints the load table: A tool for observing the state of the system.

Precondition:: None

Postcondition:: None

Limitations:: Some entries in Load table could become stale relative to the global state. The definition of Supply/Normal/Demand could change in future

ModuleMessage freedm::broker::lb::LBAgent::MessageCollectedState ( float state )

private

MessageCollectedState

Description:: Given a state, return a message that announces that new state.

Precondition:: none

Postcondition:: returns a new message

Parameters

state the normal value to send out.

ModuleMessage freedm::broker::lb::LBAgent::MessageDraftAccept ( float amount )

private

MessageDraftAccept

Description:: Generates a new accept message

Precondition:: None

Postcondition:: an Accept message is generated.

ModuleMessage freedm::broker::lb::LBAgent::MessageDraftAge ( float age )

private

MessageDraftAge

Precondition:: None

Postcondition:: A new message is generated

Description:: Creates a new DraftAge message.

ModuleMessage freedm::broker::lb::LBAgent::MessageDraftRequest ( )

private

MessageDraftRequest

Precondition:: None

Postcondition:: A new message is generated

Description:: Creates a new DraftRequest message.

ModuleMessage freedm::broker::lb::LBAgent::MessageDraftSelect ( float amount )

private

MessageDrafting

Description:: Generates a new DraftSelect message.

Precondition:: None

Postcondition:: a new message is generated.

ModuleMessage freedm::broker::lb::LBAgent::MessageStateChange ( std::string state )

private

MessageStateChange

Description:: Generates a state change message

Precondition:: None

Postcondition:: Returns the new message.

Parameters

state is a string describing the new state of Load Balancing

ModuleMessage freedm::broker::lb::LBAgent::MessageStateCollection ( )

private

MessageStateCollection

Description:: Returns a message which is sent to state collection requesting that state collection runs for the given devices.

Precondition:: None

Postcondition:: A CollectState message is created.

ModuleMessage freedm::broker::lb::LBAgent::MessageTooLate ( float amount )

private

MessageTooLate

Description:: Generates a new too late message

Precondition:: None

Postcondition:: A too late message is generated.

void freedm::broker::lb::LBAgent::MoveToPeerSet	(	PeerSet &	ps,
		CPeerNode	peer
	)

private

MoveToPeerSet Moves the given peer to the given peerset, removing it from all other categorized peersets (Normal, Supply Demand).

Precondition:: None

Postcondition:: Peer is removed from all specialized peersets, and then readded to ps.

Parameters

ps	The peerset to move the peer to.
peer	the peer to move.

ModuleMessage freedm::broker::lb::LBAgent::PrepareForSending	(	const LoadBalancingMessage &	m,
		std::string	recipient = `"lb"`
	)

private

Wraps a LoadBalancingMessage in a ModuleMessage.

Parameters

m	the message to prepare. If any required field is unset, the DGI will abort.
recipient	the module (sc/lb/gm/clk etc.) the message should be delivered to

Returns: a ModuleMessage containing a copy of the LoadBalancingMessage

void freedm::broker::lb::LBAgent::ReadDevices ( )

private

ReadDevices

Description:: Reads the device state and updates the appropriate member vars.

Precondition:: None

Postcondition:: m_gateway and m_netgeneration are updated.

int freedm::broker::lb::LBAgent::Run ( )

Run

Description:: Main function which initiates the algorithm

Precondition:: : Posix Main should invoke this function

Postcondition:: : Triggers the drafting algorithm by calling LoadManage()

Limitations:: None

void freedm::broker::lb::LBAgent::ScheduleNextRound ( )

private

ScheduleNextRound

Description:: Computes how much time is remaining and if there isn't enough requests the loadbalance that will run next round.

Precondition:: None

Postcondition:: LoadManage is scheduled for this round OR FirstRound is scheduled for next time.

void freedm::broker::lb::LBAgent::ScheduleStateCollection ( )

private

ScheduleStateCollection

Description:: Sends the request to the state collection module to perform state collection

Precondition:: None

Postcondition:: If this node is the leader a state collection request is sent.

void freedm::broker::lb::LBAgent::SendDraftAccept	(	CPeerNode	peer,
		float	step
	)

private

void freedm::broker::lb::LBAgent::SendDraftAge ( CPeerNode peer )

private

SendDraftAge

Description:: Sends a DraftAge message to specified peer announcing how much demand this node has.

Parameters

peer	The process to send this to.

Precondition:: None

Postcondition:: Sends a DraftAge message if this process was in the demand state.

void freedm::broker::lb::LBAgent::SendDraftRequest ( )

private

SendDraftRequest

Description:: Advertise willingness to share load whenever you can supply

Precondition:: : Current load state of this node is 'Supply'

Postcondition:: : Send DraftRequest message to peers in demand state

void freedm::broker::lb::LBAgent::SendDraftSelect	(	CPeerNode	peer,
		float	step
	)

private

SendDraftSelect

Description:: Sends a DraftSelect Message to specified peer.

Precondition:: Peer and step are valid

Postcondition:: A Draft select emssage is sent to the peer

void freedm::broker::lb::LBAgent::SendTooLate	(	CPeerNode	peer,
		float	step
	)

private

void freedm::broker::lb::LBAgent::SendToPeerSet	(	const PeerSet &	ps,
		const ModuleMessage &	m
	)

private

SendToPeerSet

Description:: Given a message m, send it to every process in peerSet

Precondition:: None

Postcondition:: m is sent to all processes in peerSet

Interaction Peers:: peerSet

Parameters

m	The message to send
ps	the processes to send the message to.

void freedm::broker::lb::LBAgent::SetDESD ( float desdv )

private

SetDesd

Description:: Migrates power by adjusting the gateway settings of the attched Desds

Precondition:: : Current load state of this node is 'Supply' or 'Demand'

Postcondition:: : Set command(s) to Desd

Parameters

Desd	the new desd setting to use.

void freedm::broker::lb::LBAgent::SetPStar ( float pstar )

private

SetPStar

Description:: Migrates power by adjusting the gateway settings of the attched SSTs

Precondition:: : Current load state of this node is 'Supply' or 'Demand'

Postcondition:: : Set command(s) to SST

Parameters

pstar the new pstar setting to use.

void freedm::broker::lb::LBAgent::Synchronize ( float k )

private

Synchronize

Description:: Sets the start of phase values for member variables using the results obtained from state collection.

Precondition:: none

Postcondition:: sets the value of m_PowerDifferential and m_PredictedGateway

Parameters

k	The new value to use for m_PowerDifferential

void freedm::broker::lb::LBAgent::UpdateState ( )

private

UpdateState

Description:: Determines the state of this node with respect to Supply, Demand, Normal.

Precondition:: The values used such as the gateway and migration step are valid and up to date.

Postcondition:: This node may change state.

Member Data Documentation

PeerSet freedm::broker::lb::LBAgent::m_AllPeers

private

std::map<std::string, float> freedm::broker::lb::LBAgent::m_DraftAge

private

float freedm::broker::lb::LBAgent::m_Gateway

private

PeerSet freedm::broker::lb::LBAgent::m_InDemand

private

PeerSet freedm::broker::lb::LBAgent::m_InNormal

private

PeerSet freedm::broker::lb::LBAgent::m_InSupply

private

std::string freedm::broker::lb::LBAgent::m_Leader

private

float freedm::broker::lb::LBAgent::m_MigrationStep

private

float freedm::broker::lb::LBAgent::m_NetGeneration

private

float freedm::broker::lb::LBAgent::m_PowerDifferential

private

float freedm::broker::lb::LBAgent::m_PredictedGateway

private

CBroker::TimerHandle freedm::broker::lb::LBAgent::m_RoundTimer

private

State freedm::broker::lb::LBAgent::m_State

private

bool freedm::broker::lb::LBAgent::m_Synchronized

private

CBroker::TimerHandle freedm::broker::lb::LBAgent::m_WaitTimer

private

const boost::posix_time::time_duration freedm::broker::lb::LBAgent::REQUEST_TIMEOUT

private

const boost::posix_time::time_duration freedm::broker::lb::LBAgent::ROUND_TIME

private

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

/home/docs/checkouts/readthedocs.org/user_builds/freedm/checkouts/latest/Broker/src/lb/LoadBalance.hpp
/home/docs/checkouts/readthedocs.org/user_builds/freedm/checkouts/latest/Broker/src/lb/LoadBalance.cpp

Public Member Functions

Protected Member Functions

Private Types

Private Member Functions

Private Attributes

Member Enumeration Documentation

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation