func AddSelfToTopology(cm *ConnectionManager, conns map[common.RMId]paxos.Connection, topology *server.Topology, fInc int, active, passive []common.RMId, lc *client.LocalConnection) (*server.Topology, bool, error) {
seg := capn.NewBuffer(nil)
txn := msgs.NewTxn(seg)
txn.SetSubmitter(uint32(cm.RMId))
txn.SetSubmitterBootCount(cm.BootCount)
actions := msgs.NewActionList(seg, 1)
txn.SetActions(actions)
topologyAction := actions.At(0)
topologyAction.SetVarId(server.TopologyVarUUId[:])
topologyAction.SetReadwrite()
rw := topologyAction.Readwrite()
rw.SetVersion(topology.DBVersion[:])
rw.SetValue(topology.Serialize())
if topology.RootVarUUId == nil {
rw.SetReferences(msgs.NewVarIdPosList(seg, 0))
} else {
refs := msgs.NewVarIdPosList(seg, 1)
rw.SetReferences(refs)
varIdPos := refs.At(0)
varIdPos.SetId(topology.RootVarUUId[:])
varIdPos.SetPositions((capn.UInt8List)(*topology.RootPositions))
}
allocs := msgs.NewAllocationList(seg, len(topology.AllRMs))
txn.SetAllocations(allocs)
idx := 0
for listIdx, rmIds := range [][]common.RMId{active, passive} {
for _, rmId := range rmIds {
alloc := allocs.At(idx)
idx++
alloc.SetRmId(uint32(rmId))
if listIdx == 0 {
alloc.SetActive(conns[rmId].BootCount())
} else {
alloc.SetActive(0)
}
indices := seg.NewUInt16List(1)
alloc.SetActionIndices(indices)
indices.Set(0, 0)
}
}
txn.SetFInc(uint8(fInc))
txn.SetTopologyVersion(topology.Version)
result, err := lc.RunTransaction(&txn, true, active...)
if err != nil || result == nil {
return nil, false, err
}
txnId := common.MakeTxnId(result.Txn().Id())
if result.Which() == msgs.OUTCOME_COMMIT {
topology.DBVersion = txnId
server.Log("Topology Txn Committed ok with txnId", topology.DBVersion)
return topology, false, nil
}
abort := result.Abort()
server.Log("Topology Txn Aborted", txnId)
if abort.Which() == msgs.OUTCOMEABORT_RESUBMIT {
return nil, true, nil
}
abortUpdates := abort.Rerun()
if abortUpdates.Len() != 1 {
return nil, false, fmt.Errorf("Internal error: readwrite of topology gave %v updates (1 expected)", abortUpdates.Len())
}
update := abortUpdates.At(0)
dbversion := common.MakeTxnId(update.TxnId())
updateActions := update.Actions()
if updateActions.Len() != 1 && updateActions.Len() != 2 {
return nil, false, fmt.Errorf("Internal error: readwrite of topology gave multiple actions: %v", updateActions.Len())
}
var updateAction *msgs.Action
for idx, l := 0, updateActions.Len(); idx < l; idx++ {
action := updateActions.At(idx)
if bytes.Equal(action.VarId(), server.TopologyVarUUId[:]) {
updateAction = &action
break
}
}
if updateAction == nil {
return nil, false, fmt.Errorf("Internal error: unable to find action for topology from readwrite")
}
if updateAction.Which() != msgs.ACTION_WRITE {
return nil, false, fmt.Errorf("Internal error: readwrite of topology gave non-write action")
}
write := updateAction.Write()
var rootVarPos *msgs.VarIdPos
if refs := write.References(); refs.Len() == 1 {
root := refs.At(0)
rootVarPos = &root
} else if refs.Len() > 1 {
return nil, false, fmt.Errorf("Internal error: readwrite of topology had wrong references: %v", refs.Len())
}
topology, err = server.TopologyDeserialize(dbversion, rootVarPos, write.Value())
if err != nil {
return nil, false, err
}
found := false
for _, rmId := range topology.AllRMs {
if found = rmId == cm.RMId; found {
server.Log("Topology Txn Aborted, but found self in topology.")
return topology, false, nil
}
}
return topology, true, nil
}
func GetTopologyFromLocalDatabase(cm *ConnectionManager, varDispatcher *eng.VarDispatcher, lc *client.LocalConnection) (*server.Topology, error) {
if paxos.IsDatabaseClean(varDispatcher) {
return nil, nil
}
for {
seg := capn.NewBuffer(nil)
txn := msgs.NewTxn(seg)
txn.SetSubmitter(uint32(cm.RMId))
txn.SetSubmitterBootCount(cm.BootCount)
actions := msgs.NewActionList(seg, 1)
txn.SetActions(actions)
action := actions.At(0)
action.SetVarId(server.TopologyVarUUId[:])
action.SetRead()
action.Read().SetVersion(common.VersionZero[:])
allocs := msgs.NewAllocationList(seg, 1)
txn.SetAllocations(allocs)
alloc := allocs.At(0)
alloc.SetRmId(uint32(cm.RMId))
alloc.SetActive(cm.BootCount)
indices := seg.NewUInt16List(1)
alloc.SetActionIndices(indices)
indices.Set(0, 0)
txn.SetFInc(1)
txn.SetTopologyVersion(0)
result, err := lc.RunTransaction(&txn, true, cm.RMId)
if err != nil {
return nil, err
}
if result == nil {
return nil, nil // shutting down
}
if result.Which() == msgs.OUTCOME_COMMIT {
return nil, fmt.Errorf("Internal error: read of topology version 0 failed to abort")
}
abort := result.Abort()
if abort.Which() == msgs.OUTCOMEABORT_RESUBMIT {
continue
}
abortUpdates := abort.Rerun()
if abortUpdates.Len() != 1 {
return nil, fmt.Errorf("Internal error: read of topology version 0 gave multiple updates")
}
update := abortUpdates.At(0)
dbversion := common.MakeTxnId(update.TxnId())
updateActions := update.Actions()
if updateActions.Len() != 1 && updateActions.Len() != 2 {
return nil, fmt.Errorf("Internal error: read of topology version 0 gave multiple actions: %v", updateActions.Len())
}
var updateAction *msgs.Action
for idx, l := 0, updateActions.Len(); idx < l; idx++ {
action := updateActions.At(idx)
if bytes.Equal(action.VarId(), server.TopologyVarUUId[:]) {
updateAction = &action
break
}
}
if updateAction == nil {
return nil, fmt.Errorf("Internal error: unable to find action for topology from read of topology version 0")
}
if updateAction.Which() != msgs.ACTION_WRITE {
return nil, fmt.Errorf("Internal error: read of topology version 0 gave non-write action")
}
write := updateAction.Write()
var rootPtr *msgs.VarIdPos
if refs := write.References(); refs.Len() == 1 {
root := refs.At(0)
rootPtr = &root
}
return server.TopologyDeserialize(dbversion, rootPtr, write.Value())
}
}
func (s *server) start() {
procs := runtime.NumCPU()
if procs < 2 {
procs = 2
}
runtime.GOMAXPROCS(procs)
disk, err := mdbs.NewMDBServer(s.dataDir, mdb.WRITEMAP, 0600, goshawk.OneTB, procs/2, time.Millisecond, db.DB)
s.maybeShutdown(err)
s.addOnShutdown(disk.Shutdown)
cm, lc := network.NewConnectionManager(s.rmId, s.bootCount, procs, disk, s.passwordHash)
s.connectionManager = cm
s.addOnShutdown(cm.Shutdown)
s.addOnShutdown(lc.Shutdown)
s.Add(1)
go s.signalHandler()
topologyLocal, err := network.GetTopologyFromLocalDatabase(cm, cm.Dispatchers.VarDispatcher, lc)
s.maybeShutdown(err)
topology, err := s.chooseTopology(topologyLocal)
s.maybeShutdown(err)
if topologyLocal == nil {
topologyTxnId, err := network.CreateTopologyZero(cm, topology, lc)
s.maybeShutdown(err)
topology.DBVersion = topologyTxnId
}
cm.SetTopology(topology)
cm.Dispatchers.VarDispatcher.ApplyToVar(func(v *eng.Var, err error) {
if err != nil {
log.Println("Error trying to subscribe to topology:", err)
return
}
emptyTxnId := common.MakeTxnId([]byte{})
v.AddWriteSubscriber(emptyTxnId,
func(v *eng.Var, value []byte, refs *msgs.VarIdPos_List, txn *eng.Txn) {
var rootVarPosPtr *msgs.VarIdPos
if refs.Len() == 1 {
root := refs.At(0)
rootVarPosPtr = &root
}
topology, err := goshawk.TopologyDeserialize(txn.Id, rootVarPosPtr, value)
if err != nil {
log.Println("Unable to deserialize new topology:", err)
}
cm.SetTopology(topology)
disk.WithEnv(func(env *mdb.Env) (interface{}, error) {
return nil, env.SetFlags(mdb.MAPASYNC, topology.AsyncFlush)
})
})
}, false, goshawk.TopologyVarUUId)
cm.AddSender(network.NewTopologyWriter(topology, lc, cm))
localHost, remoteHosts, err := topology.LocalRemoteHosts(s.port)
s.maybeShutdown(err)
log.Printf(">==> We are %v (%v) <==<\n", localHost, s.rmId)
listener, err := network.NewListener(s.port, cm)
s.maybeShutdown(err)
s.addOnShutdown(listener.Shutdown)
cm.SetDesiredServers(localHost, remoteHosts)
defer s.shutdown(nil)
s.Wait()
}