Ejemplo n.º 1
0
// ContinuousDiscovery starts an asynchronuous infinite discovery process where instances are
// periodically investigated and their status captured, and long since unseen instances are
// purged and forgotten.
func ContinuousDiscovery() {
	if config.Config.DatabaselessMode__experimental {
		log.Fatal("Cannot execute continuous mode in databaseless mode")
	}

	log.Infof("Starting continuous discovery")
	recentDiscoveryOperationKeys = cache.New(time.Duration(config.Config.InstancePollSeconds)*time.Second, time.Second)

	inst.LoadHostnameResolveCache()
	go handleDiscoveryRequests()

	discoveryTick := time.Tick(time.Duration(config.Config.GetDiscoveryPollSeconds()) * time.Second)
	instancePollTick := time.Tick(time.Duration(config.Config.InstancePollSeconds) * time.Second)
	caretakingTick := time.Tick(time.Minute)
	recoveryTick := time.Tick(time.Duration(config.Config.RecoveryPollSeconds) * time.Second)
	var snapshotTopologiesTick <-chan time.Time
	if config.Config.SnapshotTopologiesIntervalHours > 0 {
		snapshotTopologiesTick = time.Tick(time.Duration(config.Config.SnapshotTopologiesIntervalHours) * time.Hour)
	}

	go ometrics.InitGraphiteMetrics()
	go acceptSignals()

	if *config.RuntimeCLIFlags.GrabElection {
		process.GrabElection()
	}
	for {
		select {
		case <-discoveryTick:
			go func() {
				wasAlreadyElected := atomic.LoadInt64(&isElectedNode)
				myIsElectedNode, err := process.AttemptElection()
				if err != nil {
					log.Errore(err)
				}
				if myIsElectedNode {
					atomic.StoreInt64(&isElectedNode, 1)
				} else {
					atomic.StoreInt64(&isElectedNode, 0)
				}

				if myIsElectedNode {
					instanceKeys, err := inst.ReadOutdatedInstanceKeys()
					if err != nil {
						log.Errore(err)
					}

					log.Debugf("outdated keys: %+v", instanceKeys)
					for _, instanceKey := range instanceKeys {
						instanceKey := instanceKey

						if instanceKey.IsValid() {
							discoveryQueue.Push(instanceKey)
						}
					}
					if wasAlreadyElected == 0 {
						// Just turned to be leader!
						go process.RegisterNode("", "", false)
					}
				} else {
					log.Debugf("Not elected as active node; polling")
				}
			}()
		case <-instancePollTick:
			go func() {
				// This tick does NOT do instance poll (these are handled by the oversmapling discoveryTick)
				// But rather should invoke such routinely operations that need to be as (or roughly as) frequent
				// as instance poll
				if atomic.LoadInt64(&isElectedNode) == 1 {
					go inst.UpdateInstanceRecentRelaylogHistory()
					go inst.RecordInstanceCoordinatesHistory()
				}
			}()
		case <-caretakingTick:
			// Various periodic internal maintenance tasks
			go func() {
				if atomic.LoadInt64(&isElectedNode) == 1 {
					go inst.RecordInstanceBinlogFileHistory()
					go inst.ForgetLongUnseenInstances()
					go inst.ForgetUnseenInstancesDifferentlyResolved()
					go inst.ForgetExpiredHostnameResolves()
					go inst.DeleteInvalidHostnameResolves()
					go inst.ReviewUnseenInstances()
					go inst.InjectUnseenMasters()
					go inst.ResolveUnknownMasterHostnameResolves()
					go inst.UpdateClusterAliases()
					go inst.ExpireMaintenance()
					go inst.ExpireDowntime()
					go inst.ExpireCandidateInstances()
					go inst.ExpireHostnameUnresolve()
					go inst.ExpireClusterDomainName()
					go inst.ExpireAudit()
					go inst.ExpireMasterPositionEquivalence()
					go inst.ExpirePoolInstances()
					go inst.FlushNontrivialResolveCacheToDatabase()
					go process.ExpireNodesHistory()
					go process.ExpireAccessTokens()
				} else {
					// Take this opportunity to refresh yourself
					go inst.LoadHostnameResolveCache()
				}
			}()
		case <-recoveryTick:
			go func() {
				if atomic.LoadInt64(&isElectedNode) == 1 {
					go ClearActiveFailureDetections()
					go ClearActiveRecoveries()
					go ExpireBlockedRecoveries()
					go AcknowledgeCrashedRecoveries()
					go inst.ExpireInstanceAnalysisChangelog()
					go CheckAndRecover(nil, nil, false)
				}
			}()
		case <-snapshotTopologiesTick:
			go func() {
				go inst.SnapshotTopologies()
			}()
		}
	}
}
Ejemplo n.º 2
0
// ContinuousDiscovery starts an asynchronuous infinite discovery process where instances are
// periodically investigated and their status captured, and long since unseen instances are
// purged and forgotten.
func ContinuousDiscovery() {
	if config.Config.DatabaselessMode__experimental {
		log.Fatal("Cannot execute continuous mode in databaseless mode")
	}

	log.Infof("Starting continuous discovery")
	inst.LoadHostnameResolveCacheFromDatabase()
	go handleDiscoveryRequests()

	discoveryTick := time.Tick(time.Duration(config.Config.DiscoveryPollSeconds) * time.Second)
	caretakingTick := time.Tick(time.Minute)
	recoveryTick := time.Tick(time.Duration(config.Config.RecoveryPollSeconds) * time.Second)
	var snapshotTopologiesTick <-chan time.Time
	if config.Config.SnapshotTopologiesIntervalHours > 0 {
		snapshotTopologiesTick = time.Tick(time.Duration(config.Config.SnapshotTopologiesIntervalHours) * time.Hour)
	}

	go ometrics.InitGraphiteMetrics()
	go acceptSignals()

	for {
		select {
		case <-discoveryTick:
			go func() {
				wasAlreadyElected := isElectedNode
				if isElectedNode, _ = process.AttemptElection(); isElectedNode {
					instanceKeys, _ := inst.ReadOutdatedInstanceKeys()
					log.Debugf("outdated keys: %+v", instanceKeys)
					for _, instanceKey := range instanceKeys {
						go func() { discoveryInstanceKeys <- instanceKey }()
					}
					if !wasAlreadyElected {
						// Just turned to be leader!
						go process.RegisterNode("", "", false)
					}
				} else {
					log.Debugf("Not elected as active node; polling")
				}
			}()
		case <-caretakingTick:
			// Various periodic internal maintenance tasks
			go func() {
				if isElectedNode {
					go inst.ForgetLongUnseenInstances()
					go inst.ForgetUnseenInstancesDifferentlyResolved()
					go inst.ForgetExpiredHostnameResolves()
					go inst.DeleteInvalidHostnameResolves()
					go inst.ReviewUnseenInstances()
					go inst.InjectUnseenMasters()
					go inst.ResolveUnknownMasterHostnameResolves()
					go inst.UpdateClusterAliases()
					go inst.ExpireMaintenance()
					go inst.ExpireDowntime()
					go inst.ExpireCandidateInstances()
					go inst.ExpireHostnameUnresolve()
					go inst.ExpireClusterDomainName()
					go inst.ExpireAudit()
					go inst.ExpireMasterPositionEquivalence()
					go inst.FlushNontrivialResolveCacheToDatabase()
					go process.ExpireNodesHistory()
				}
				if !isElectedNode {
					// Take this opportunity to refresh yourself
					go inst.LoadHostnameResolveCacheFromDatabase()
				}
				go inst.ReadClusterAliases()
			}()
		case <-recoveryTick:
			go func() {
				if isElectedNode {
					go ClearActiveFailureDetections()
					go ClearActiveRecoveries()
					go ExpireBlockedRecoveries()
					go AcknowledgeCrashedRecoveries()
					go inst.ExpireInstanceAnalysisChangelog()
					go CheckAndRecover(nil, nil, false)
				}
			}()
		case <-snapshotTopologiesTick:
			go func() {
				go inst.SnapshotTopologies()
			}()
		}
	}
}