func (r *raftNode) run() {
var syncC <-chan time.Time
defer r.stop()
for {
select {
case <-r.ticker:
r.Tick()
case rd := <-r.Ready():
if rd.SoftState != nil {
atomic.StoreUint64(&r.lead, rd.SoftState.Lead)
if rd.RaftState == raft.StateLeader {
syncC = r.s.SyncTicker
// TODO: remove the nil checking
// current test utility does not provide the stats
if r.s.stats != nil {
r.s.stats.BecomeLeader()
}
} else {
syncC = nil
}
}
apply := apply{
entries: rd.CommittedEntries,
snapshot: rd.Snapshot,
done: make(chan struct{}),
}
select {
case r.applyc <- apply:
case <-r.s.done:
return
}
if !raft.IsEmptySnap(rd.Snapshot) {
if err := r.storage.SaveSnap(rd.Snapshot); err != nil {
log.Fatalf("etcdraft: save snapshot error: %v", err)
}
r.raftStorage.ApplySnapshot(rd.Snapshot)
log.Printf("etcdraft: applied incoming snapshot at index %d", rd.Snapshot.Metadata.Index)
}
if err := r.storage.Save(rd.HardState, rd.Entries); err != nil {
log.Fatalf("etcdraft: save state and entries error: %v", err)
}
r.raftStorage.Append(rd.Entries)
r.s.send(rd.Messages)
<-apply.done
r.Advance()
case <-syncC:
r.s.sync(defaultSyncTimeout)
case <-r.s.done:
return
}
}
}
func (s *EtcdServer) run() {
snap, err := s.r.raftStorage.Snapshot()
if err != nil {
log.Panicf("etcdserver: get snapshot from raft storage error: %v", err)
}
confState := snap.Metadata.ConfState
snapi := snap.Metadata.Index
appliedi := snapi
// TODO: get rid of the raft initialization in etcd server
s.r.s = s
s.r.applyc = make(chan apply)
go s.r.run()
defer close(s.done)
var shouldstop bool
for {
select {
case apply := <-s.r.apply():
// apply snapshot
if !raft.IsEmptySnap(apply.snapshot) {
if apply.snapshot.Metadata.Index <= appliedi {
log.Panicf("etcdserver: snapshot index [%d] should > appliedi[%d] + 1",
apply.snapshot.Metadata.Index, appliedi)
}
if err := s.store.Recovery(apply.snapshot.Data); err != nil {
log.Panicf("recovery store error: %v", err)
}
// Avoid snapshot recovery overwriting newer cluster and
// transport setting, which may block the communication.
if s.Cluster.index < apply.snapshot.Metadata.Index {
s.Cluster.Recover()
// recover raft transport
s.r.transport.RemoveAllPeers()
for _, m := range s.Cluster.Members() {
if m.ID == s.ID() {
continue
}
s.r.transport.AddPeer(m.ID, m.PeerURLs)
}
}
appliedi = apply.snapshot.Metadata.Index
snapi = appliedi
confState = apply.snapshot.Metadata.ConfState
log.Printf("etcdserver: recovered from incoming snapshot at index %d", snapi)
}
// apply entries
if len(apply.entries) != 0 {
firsti := apply.entries[0].Index
if firsti > appliedi+1 {
log.Panicf("etcdserver: first index of committed entry[%d] should <= appliedi[%d] + 1", firsti, appliedi)
}
var ents []raftpb.Entry
if appliedi+1-firsti < uint64(len(apply.entries)) {
ents = apply.entries[appliedi+1-firsti:]
}
if appliedi, shouldstop = s.apply(ents, &confState); shouldstop {
go s.stopWithDelay(10*100*time.Millisecond, fmt.Errorf("the member has been permanently removed from the cluster"))
}
}
// wait for the raft routine to finish the disk writes before triggering a
// snapshot. or applied index might be greater than the last index in raft
// storage, since the raft routine might be slower than apply routine.
apply.done <- struct{}{}
// trigger snapshot
if appliedi-snapi > s.snapCount {
log.Printf("etcdserver: start to snapshot (applied: %d, lastsnap: %d)", appliedi, snapi)
s.snapshot(appliedi, confState)
snapi = appliedi
}
case err := <-s.errorc:
log.Printf("etcdserver: %s", err)
log.Printf("etcdserver: the data-dir used by this member must be removed.")
return
case <-s.stop:
return
}
}
// TODO: wait for the stop of raft node routine?
}
func (s *Snapshotter) SaveSnap(snapshot raftpb.Snapshot) error {
if raft.IsEmptySnap(snapshot) {
return nil
}
return s.save(&snapshot)
}