func (s *Server) generateViewSequenceWithConsensus(associatedView *view.View, seq ViewSeq) {
assertOnlyUpdatedViews(associatedView, seq)
if associatedView.GetProcessPosition(s.thisProcess) == CONSENSUS_LEADER_PROCESS_POSITION {
consensus.Propose(associatedView, s.thisProcess, &seq)
}
log.Println("Waiting for consensus resolution")
value := <-consensus.GetConsensusResultChan(associatedView)
// get startReconfigurationTime to compute reconfiguration duration
//if startReconfigurationTime.IsZero() || startReconfigurationTime.Sub(time.Now()) > 20*time.Second {
//startReconfigurationTime = consensus.GetConsensusStartTime(associatedView)
//log.Println("starttime :", startReconfigurationTime)
//}
result, ok := value.(*ViewSeq)
if !ok {
log.Fatalf("FATAL: consensus on generateViewSequenceWithConsensus got %T %v\n", value, value)
}
log.Println("Consensus result received")
s.generatedViewSeqChan <- generatedViewSeq{
AssociatedView: associatedView,
ViewSeq: *result,
}
}
func broadcastAcceptRequest(destinationView *view.View, proposal Proposal, resultChan chan Proposal) {
for _, process := range destinationView.GetMembers() {
go func(process view.Process) {
var result Proposal
err := comm.SendRPCRequest(process, "ConsensusRequest.Accept", proposal, &result)
if err != nil {
resultChan <- Proposal{Err: err}
return
}
resultChan <- result
}(process)
}
}
func (s *Server) updateCurrentViewLocked(newView *view.View) {
if !newView.MoreUpdatedThan(s.currentView) {
// comment these log messages; they are just for debugging
if newView.LessUpdatedThan(s.currentView) {
log.Println("WARNING: Tried to Update current view with a less updated view")
} else {
log.Println("WARNING: Tried to Update current view with the same view")
}
return
}
s.currentView = newView
log.Printf("CurrentView updated to: %v, ref: %v\n", s.currentView, s.currentView.ViewRef)
}
// BroadcastRPCRequest invokes serviceMethod at all members of the
// destinationView with arg. It returns an error if it fails to receive
// a response from a quorum of processes.
func BroadcastRPCRequest(destinationView *view.View, serviceMethod string, arg interface{}) error {
errorChan := make(chan error, destinationView.NumberOfMembers())
for _, process := range destinationView.GetMembers() {
go func(process view.Process) {
var discardResult struct{}
errorChan <- SendRPCRequest(process, serviceMethod, arg, &discardResult)
}(process)
}
failedTotal := 0
successTotal := 0
for {
err := <-errorChan
if err != nil {
failedTotal++
if failedTotal > destinationView.NumberOfToleratedFaults() {
log.Printf("WARN: BroadcastRPCRequest failed to send %v to a quorum\n", serviceMethod)
return err
}
} else {
successTotal++
if successTotal == destinationView.QuorumSize() {
return nil
}
}
}
}
func getOrCreateConsensus(associatedView *view.View) consensusInstance {
consensusTableMu.Lock()
defer consensusTableMu.Unlock()
ci, ok := consensusTable[associatedView.NumberOfUpdates()]
if !ok {
ci = consensusInstance{associatedView: associatedView, taskChan: make(chan consensusTask, CHANNEL_DEFAULT_BUFFER_SIZE), callbackLearnChan: make(chan interface{}, 1)}
//ci.startTime = time.Now()
consensusTable[associatedView.NumberOfUpdates()] = ci
log.Println("Created consensus instance:", ci)
go consensusWorker(ci)
}
return ci
}
func broadcastWrite(destinationView *view.View, writeMsg RegisterMsg, resultChan chan RegisterMsg) {
for _, process := range destinationView.GetMembers() {
go sendWrite(process, &writeMsg, resultChan)
}
}
func broadcastRead(destinationView *view.View, viewRef view.ViewRef, resultChan chan RegisterMsg) {
for _, process := range destinationView.GetMembers() {
go sendRead(process, viewRef, resultChan)
}
}
// getNextProposalNumber to be used by this process. This function is a stage of the Propose funcion.
func getNextProposalNumber(associatedView *view.View, thisProcess view.Process) (proposalNumber int) {
if associatedView.NumberOfMembers() == 0 {
log.Fatalln("associatedView is empty")
}
thisProcessPosition := associatedView.GetProcessPosition(thisProcess)
lastProposalNumber, err := getLastProposalNumber(associatedView.NumberOfUpdates())
if err != nil {
proposalNumber = associatedView.NumberOfMembers() + thisProcessPosition
} else {
proposalNumber = (lastProposalNumber - (lastProposalNumber % associatedView.NumberOfMembers()) + associatedView.NumberOfMembers()) + thisProcessPosition
}
saveProposalNumberOnStorage(associatedView.NumberOfUpdates(), proposalNumber)
return
}
// -------- Broadcast functions -----------
func broadcastViewSequence(destinationView *view.View, viewSeqMsg ViewSeqMsg) {
destinationViewWithoutThisProcess := destinationView.NewCopyWithUpdates(view.Update{Type: view.Leave, Process: globalServer.thisProcess})
comm.BroadcastRPCRequest(destinationViewWithoutThisProcess, "ViewGeneratorRequest.ProposeSeqView", viewSeqMsg)
}