mirror of
https://github.com/etcd-io/etcd.git
synced 2024-09-27 06:25:44 +00:00
Merge pull request #2004 from xiang90/status
raft: add Status interface
This commit is contained in:
commit
7c7d78a11f
@ -1300,15 +1300,18 @@ func (n *nodeRecorder) Step(ctx context.Context, msg raftpb.Message) error {
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n.Record(testutil.Action{Name: "Step"})
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return nil
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}
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func (n *nodeRecorder) Status() raft.Status { return raft.Status{} }
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func (n *nodeRecorder) Ready() <-chan raft.Ready { return nil }
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func (n *nodeRecorder) Advance() {}
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func (n *nodeRecorder) ApplyConfChange(conf raftpb.ConfChange) *raftpb.ConfState {
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n.Record(testutil.Action{Name: "ApplyConfChange", Params: []interface{}{conf}})
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return &raftpb.ConfState{}
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}
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func (n *nodeRecorder) Stop() {
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n.Record(testutil.Action{Name: "Stop"})
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}
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func (n *nodeRecorder) Compact(index uint64, nodes []uint64, d []byte) {
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n.Record(testutil.Action{Name: "Compact"})
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}
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15
raft/node.go
15
raft/node.go
@ -119,6 +119,8 @@ type Node interface {
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// in snapshots. Will never return nil; it returns a pointer only
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// to match MemoryStorage.Compact.
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ApplyConfChange(cc pb.ConfChange) *pb.ConfState
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// Status returns the current status of the raft state machine.
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Status() Status
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// Stop performs any necessary termination of the Node
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Stop()
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}
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@ -190,6 +192,7 @@ type node struct {
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tickc chan struct{}
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done chan struct{}
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stop chan struct{}
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status chan chan Status
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}
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func newNode() node {
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@ -203,6 +206,7 @@ func newNode() node {
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tickc: make(chan struct{}),
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done: make(chan struct{}),
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stop: make(chan struct{}),
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status: make(chan chan Status),
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}
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}
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@ -222,8 +226,7 @@ func (n *node) run(r *raft) {
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var propc chan pb.Message
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var readyc chan Ready
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var advancec chan struct{}
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var prevLastUnstablei uint64
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var prevLastUnstablet uint64
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var prevLastUnstablei, prevLastUnstablet uint64
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var havePrevLastUnstablei bool
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var prevSnapi uint64
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var rd Ready
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@ -328,6 +331,8 @@ func (n *node) run(r *raft) {
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}
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r.raftLog.stableSnapTo(prevSnapi)
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advancec = nil
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case c := <-n.status:
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c <- getStatus(r)
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case <-n.stop:
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close(n.done)
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return
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@ -407,6 +412,12 @@ func (n *node) ApplyConfChange(cc pb.ConfChange) *pb.ConfState {
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return &cs
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}
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func (n *node) Status() Status {
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c := make(chan Status)
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n.status <- c
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return <-c
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}
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func newReady(r *raft, prevSoftSt *SoftState, prevHardSt pb.HardState) Ready {
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rd := Ready{
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Entries: r.raftLog.unstableEntries(),
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82
raft/raft.go
82
raft/raft.go
@ -52,61 +52,61 @@ func (st StateType) String() string {
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return stmap[uint64(st)]
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}
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type progress struct {
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match, next uint64
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wait int
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type Progress struct {
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Match, Next uint64
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Wait int
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}
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func (pr *progress) update(n uint64) {
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func (pr *Progress) update(n uint64) {
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pr.waitReset()
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if pr.match < n {
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pr.match = n
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if pr.Match < n {
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pr.Match = n
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}
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if pr.next < n+1 {
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pr.next = n + 1
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if pr.Next < n+1 {
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pr.Next = n + 1
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}
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}
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func (pr *progress) optimisticUpdate(n uint64) { pr.next = n + 1 }
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func (pr *Progress) optimisticUpdate(n uint64) { pr.Next = n + 1 }
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// maybeDecrTo returns false if the given to index comes from an out of order message.
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// Otherwise it decreases the progress next index to min(rejected, last) and returns true.
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func (pr *progress) maybeDecrTo(rejected, last uint64) bool {
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func (pr *Progress) maybeDecrTo(rejected, last uint64) bool {
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pr.waitReset()
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if pr.match != 0 {
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if pr.Match != 0 {
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// the rejection must be stale if the progress has matched and "rejected"
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// is smaller than "match".
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if rejected <= pr.match {
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if rejected <= pr.Match {
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return false
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}
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// directly decrease next to match + 1
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pr.next = pr.match + 1
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pr.Next = pr.Match + 1
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return true
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}
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// the rejection must be stale if "rejected" does not match next - 1
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if pr.next-1 != rejected {
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if pr.Next-1 != rejected {
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return false
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}
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if pr.next = min(rejected, last+1); pr.next < 1 {
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pr.next = 1
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if pr.Next = min(rejected, last+1); pr.Next < 1 {
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pr.Next = 1
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}
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return true
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}
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func (pr *progress) waitDecr(i int) {
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pr.wait -= i
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if pr.wait < 0 {
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pr.wait = 0
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func (pr *Progress) waitDecr(i int) {
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pr.Wait -= i
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if pr.Wait < 0 {
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pr.Wait = 0
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}
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}
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func (pr *progress) waitSet(w int) { pr.wait = w }
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func (pr *progress) waitReset() { pr.wait = 0 }
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func (pr *progress) shouldWait() bool { return pr.match == 0 && pr.wait > 0 }
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func (pr *Progress) waitSet(w int) { pr.Wait = w }
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func (pr *Progress) waitReset() { pr.Wait = 0 }
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func (pr *Progress) shouldWait() bool { return pr.Match == 0 && pr.Wait > 0 }
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func (pr *progress) String() string {
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return fmt.Sprintf("next = %d, match = %d, wait = %v", pr.next, pr.match, pr.wait)
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func (pr *Progress) String() string {
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return fmt.Sprintf("next = %d, match = %d, wait = %v", pr.Next, pr.Match, pr.Wait)
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}
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type raft struct {
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@ -117,7 +117,7 @@ type raft struct {
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// the log
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raftLog *raftLog
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prs map[uint64]*progress
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prs map[uint64]*Progress
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state StateType
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@ -161,13 +161,13 @@ func newRaft(id uint64, peers []uint64, election, heartbeat int, storage Storage
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id: id,
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lead: None,
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raftLog: raftlog,
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prs: make(map[uint64]*progress),
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prs: make(map[uint64]*Progress),
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electionTimeout: election,
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heartbeatTimeout: heartbeat,
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}
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r.rand = rand.New(rand.NewSource(int64(id)))
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for _, p := range peers {
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r.prs[p] = &progress{next: 1}
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r.prs[p] = &Progress{Next: 1}
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}
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if !isHardStateEqual(hs, emptyState) {
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r.loadState(hs)
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@ -220,7 +220,7 @@ func (r *raft) sendAppend(to uint64) {
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}
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m := pb.Message{}
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m.To = to
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if r.needSnapshot(pr.next) {
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if r.needSnapshot(pr.Next) {
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m.Type = pb.MsgSnap
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snapshot, err := r.raftLog.snapshot()
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if err != nil {
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@ -236,15 +236,15 @@ func (r *raft) sendAppend(to uint64) {
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pr.waitSet(r.electionTimeout)
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} else {
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m.Type = pb.MsgApp
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m.Index = pr.next - 1
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m.LogTerm = r.raftLog.term(pr.next - 1)
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m.Entries = r.raftLog.entries(pr.next)
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m.Index = pr.Next - 1
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m.LogTerm = r.raftLog.term(pr.Next - 1)
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m.Entries = r.raftLog.entries(pr.Next)
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m.Commit = r.raftLog.committed
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// optimistically increase the next if the follower
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// has been matched.
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if n := len(m.Entries); pr.match != 0 && n != 0 {
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if n := len(m.Entries); pr.Match != 0 && n != 0 {
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pr.optimisticUpdate(m.Entries[n-1].Index)
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} else if pr.match == 0 {
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} else if pr.Match == 0 {
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// TODO (xiangli): better way to find out if the follower is in good path or not
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// a follower might be in bad path even if match != 0, since we optimistically
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// increase the next.
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@ -262,7 +262,7 @@ func (r *raft) sendHeartbeat(to uint64) {
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// or it might not have all the committed entries.
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// The leader MUST NOT forward the follower's commit to
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// an unmatched index.
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commit := min(r.prs[to].match, r.raftLog.committed)
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commit := min(r.prs[to].Match, r.raftLog.committed)
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m := pb.Message{
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To: to,
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Type: pb.MsgHeartbeat,
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@ -297,7 +297,7 @@ func (r *raft) maybeCommit() bool {
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// TODO(bmizerany): optimize.. Currently naive
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mis := make(uint64Slice, 0, len(r.prs))
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for i := range r.prs {
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mis = append(mis, r.prs[i].match)
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mis = append(mis, r.prs[i].Match)
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}
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sort.Sort(sort.Reverse(mis))
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mci := mis[r.q()-1]
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@ -311,9 +311,9 @@ func (r *raft) reset(term uint64) {
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r.elapsed = 0
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r.votes = make(map[uint64]bool)
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for i := range r.prs {
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r.prs[i] = &progress{next: r.raftLog.lastIndex() + 1}
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r.prs[i] = &Progress{Next: r.raftLog.lastIndex() + 1}
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if i == r.id {
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r.prs[i].match = r.raftLog.lastIndex()
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r.prs[i].Match = r.raftLog.lastIndex()
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}
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}
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r.pendingConf = false
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@ -495,7 +495,7 @@ func stepLeader(r *raft, m pb.Message) {
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}
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}
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case pb.MsgHeartbeatResp:
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if r.prs[m.From].match < r.raftLog.lastIndex() {
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if r.prs[m.From].Match < r.raftLog.lastIndex() {
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r.sendAppend(m.From)
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}
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case pb.MsgVote:
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@ -616,7 +616,7 @@ func (r *raft) restore(s pb.Snapshot) bool {
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r.id, r.Commit, r.raftLog.lastIndex(), r.raftLog.lastTerm(), s.Metadata.Index, s.Metadata.Term)
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r.raftLog.restore(s)
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r.prs = make(map[uint64]*progress)
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r.prs = make(map[uint64]*Progress)
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for _, n := range s.Metadata.ConfState.Nodes {
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match, next := uint64(0), uint64(r.raftLog.lastIndex())+1
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if n == r.id {
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@ -660,7 +660,7 @@ func (r *raft) removeNode(id uint64) {
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func (r *raft) resetPendingConf() { r.pendingConf = false }
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func (r *raft) setProgress(id, match, next uint64) {
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r.prs[id] = &progress{next: next, match: match}
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r.prs[id] = &Progress{Next: next, Match: match}
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}
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func (r *raft) delProgress(id uint64) {
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|
@ -64,16 +64,16 @@ func TestProgressUpdate(t *testing.T) {
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{prevM + 2, prevM + 2, prevN + 1}, // increase match, next
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}
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for i, tt := range tests {
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p := &progress{
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match: prevM,
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next: prevN,
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p := &Progress{
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Match: prevM,
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Next: prevN,
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}
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p.update(tt.update)
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if p.match != tt.wm {
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t.Errorf("#%d: match= %d, want %d", i, p.match, tt.wm)
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if p.Match != tt.wm {
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t.Errorf("#%d: match= %d, want %d", i, p.Match, tt.wm)
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}
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if p.next != tt.wn {
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t.Errorf("#%d: next= %d, want %d", i, p.next, tt.wn)
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if p.Next != tt.wn {
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t.Errorf("#%d: next= %d, want %d", i, p.Next, tt.wn)
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}
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}
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}
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@ -136,17 +136,17 @@ func TestProgressMaybeDecr(t *testing.T) {
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},
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}
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for i, tt := range tests {
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p := &progress{
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match: tt.m,
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next: tt.n,
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p := &Progress{
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Match: tt.m,
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Next: tt.n,
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}
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if g := p.maybeDecrTo(tt.rejected, tt.last); g != tt.w {
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t.Errorf("#%d: maybeDecrTo= %t, want %t", i, g, tt.w)
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}
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if gm := p.match; gm != tt.m {
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if gm := p.Match; gm != tt.m {
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t.Errorf("#%d: match= %d, want %d", i, gm, tt.m)
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}
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if gn := p.next; gn != tt.wn {
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if gn := p.Next; gn != tt.wn {
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t.Errorf("#%d: next= %d, want %d", i, gn, tt.wn)
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}
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}
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@ -166,9 +166,9 @@ func TestProgressShouldWait(t *testing.T) {
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{0, 0, false},
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}
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for i, tt := range tests {
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p := &progress{
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match: tt.m,
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wait: tt.wait,
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p := &Progress{
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Match: tt.m,
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Wait: tt.wait,
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}
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if g := p.shouldWait(); g != tt.w {
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t.Errorf("#%d: shouldwait = %t, want %t", i, g, tt.w)
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@ -179,17 +179,17 @@ func TestProgressShouldWait(t *testing.T) {
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// TestProgressWaitReset ensures that progress.Update and progress.DercTo
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// will reset progress.wait.
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func TestProgressWaitReset(t *testing.T) {
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p := &progress{
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wait: 1,
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p := &Progress{
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Wait: 1,
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}
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p.maybeDecrTo(1, 1)
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if p.wait != 0 {
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t.Errorf("wait= %d, want 0", p.wait)
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if p.Wait != 0 {
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t.Errorf("wait= %d, want 0", p.Wait)
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}
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p.wait = 1
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p.Wait = 1
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p.update(2)
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if p.wait != 0 {
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t.Errorf("wait= %d, want 0", p.wait)
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if p.Wait != 0 {
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t.Errorf("wait= %d, want 0", p.Wait)
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}
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}
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@ -198,11 +198,11 @@ func TestProgressDecr(t *testing.T) {
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r := newRaft(1, []uint64{1, 2}, 5, 1, NewMemoryStorage())
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r.becomeCandidate()
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r.becomeLeader()
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r.prs[2].wait = r.heartbeatTimeout * 2
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r.prs[2].Wait = r.heartbeatTimeout * 2
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r.Step(pb.Message{From: 1, To: 1, Type: pb.MsgBeat})
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if r.prs[2].wait != r.heartbeatTimeout*(2-1) {
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t.Errorf("wait = %d, want %d", r.prs[2].wait, r.heartbeatTimeout*(2-1))
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if r.prs[2].Wait != r.heartbeatTimeout*(2-1) {
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t.Errorf("wait = %d, want %d", r.prs[2].Wait, r.heartbeatTimeout*(2-1))
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}
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}
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@ -1073,11 +1073,11 @@ func TestLeaderAppResp(t *testing.T) {
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sm.Step(pb.Message{From: 2, Type: pb.MsgAppResp, Index: tt.index, Term: sm.Term, Reject: tt.reject, RejectHint: tt.index})
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p := sm.prs[2]
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if p.match != tt.wmatch {
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t.Errorf("#%d match = %d, want %d", i, p.match, tt.wmatch)
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if p.Match != tt.wmatch {
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t.Errorf("#%d match = %d, want %d", i, p.Match, tt.wmatch)
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}
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if p.next != tt.wnext {
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t.Errorf("#%d next = %d, want %d", i, p.next, tt.wnext)
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if p.Next != tt.wnext {
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t.Errorf("#%d next = %d, want %d", i, p.Next, tt.wnext)
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}
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msgs := sm.readMessages()
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@ -1119,9 +1119,9 @@ func TestBcastBeat(t *testing.T) {
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sm.appendEntry(pb.Entry{Index: uint64(i) + 1})
|
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}
|
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// slow follower
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sm.prs[2].match, sm.prs[2].next = 5, 6
|
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sm.prs[2].Match, sm.prs[2].Next = 5, 6
|
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// normal follower
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sm.prs[3].match, sm.prs[3].next = sm.raftLog.lastIndex(), sm.raftLog.lastIndex()+1
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sm.prs[3].Match, sm.prs[3].Next = sm.raftLog.lastIndex(), sm.raftLog.lastIndex()+1
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sm.Step(pb.Message{Type: pb.MsgBeat})
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msgs := sm.readMessages()
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@ -1129,8 +1129,8 @@ func TestBcastBeat(t *testing.T) {
|
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t.Fatalf("len(msgs) = %v, want 2", len(msgs))
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}
|
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wantCommitMap := map[uint64]uint64{
|
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2: min(sm.raftLog.committed, sm.prs[2].match),
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3: min(sm.raftLog.committed, sm.prs[3].match),
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2: min(sm.raftLog.committed, sm.prs[2].Match),
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3: min(sm.raftLog.committed, sm.prs[3].Match),
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}
|
||||
for i, m := range msgs {
|
||||
if m.Type != pb.MsgHeartbeat {
|
||||
@ -1216,12 +1216,12 @@ func TestLeaderIncreaseNext(t *testing.T) {
|
||||
sm.raftLog.append(previousEnts...)
|
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sm.becomeCandidate()
|
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sm.becomeLeader()
|
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sm.prs[2].match, sm.prs[2].next = tt.match, tt.next
|
||||
sm.prs[2].Match, sm.prs[2].Next = tt.match, tt.next
|
||||
sm.Step(pb.Message{From: 1, To: 1, Type: pb.MsgProp, Entries: []pb.Entry{{Data: []byte("somedata")}}})
|
||||
|
||||
p := sm.prs[2]
|
||||
if p.next != tt.wnext {
|
||||
t.Errorf("#%d next = %d, want %d", i, p.next, tt.wnext)
|
||||
if p.Next != tt.wnext {
|
||||
t.Errorf("#%d next = %d, want %d", i, p.Next, tt.wnext)
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -1310,9 +1310,9 @@ func TestProvideSnap(t *testing.T) {
|
||||
|
||||
// force set the next of node 1, so that
|
||||
// node 1 needs a snapshot
|
||||
sm.prs[2].next = sm.raftLog.firstIndex()
|
||||
sm.prs[2].Next = sm.raftLog.firstIndex()
|
||||
|
||||
sm.Step(pb.Message{From: 2, To: 1, Type: pb.MsgAppResp, Index: sm.prs[2].next - 1, Reject: true})
|
||||
sm.Step(pb.Message{From: 2, To: 1, Type: pb.MsgAppResp, Index: sm.prs[2].Next - 1, Reject: true})
|
||||
msgs := sm.readMessages()
|
||||
if len(msgs) != 1 {
|
||||
t.Fatalf("len(msgs) = %d, want 1", len(msgs))
|
||||
@ -1547,9 +1547,9 @@ func newNetwork(peers ...Interface) *network {
|
||||
npeers[id] = sm
|
||||
case *raft:
|
||||
v.id = id
|
||||
v.prs = make(map[uint64]*progress)
|
||||
v.prs = make(map[uint64]*Progress)
|
||||
for i := 0; i < size; i++ {
|
||||
v.prs[peerAddrs[i]] = &progress{}
|
||||
v.prs[peerAddrs[i]] = &Progress{}
|
||||
}
|
||||
v.reset(0)
|
||||
npeers[id] = v
|
||||
|
49
raft/status.go
Normal file
49
raft/status.go
Normal file
@ -0,0 +1,49 @@
|
||||
/*
|
||||
Copyright 2014 CoreOS, Inc.
|
||||
|
||||
Licensed under the Apache License, Version 2.0 (the "License");
|
||||
you may not use this file except in compliance with the License.
|
||||
You may obtain a copy of the License at
|
||||
|
||||
http://www.apache.org/licenses/LICENSE-2.0
|
||||
|
||||
Unless required by applicable law or agreed to in writing, software
|
||||
distributed under the License is distributed on an "AS IS" BASIS,
|
||||
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||
See the License for the specific language governing permissions and
|
||||
limitations under the License.
|
||||
*/
|
||||
|
||||
package raft
|
||||
|
||||
import (
|
||||
pb "github.com/coreos/etcd/raft/raftpb"
|
||||
)
|
||||
|
||||
type Status struct {
|
||||
ID uint64
|
||||
|
||||
pb.HardState
|
||||
SoftState
|
||||
|
||||
Applied uint64
|
||||
Progress map[uint64]Progress
|
||||
}
|
||||
|
||||
// getStatus gets a copy of the current raft status.
|
||||
func getStatus(r *raft) Status {
|
||||
s := Status{ID: r.id}
|
||||
s.HardState = r.HardState
|
||||
s.SoftState = *r.softState()
|
||||
|
||||
s.Applied = r.raftLog.applied
|
||||
|
||||
if s.RaftState == StateLeader {
|
||||
s.Progress = make(map[uint64]Progress)
|
||||
for id, p := range r.prs {
|
||||
s.Progress[id] = *p
|
||||
}
|
||||
}
|
||||
|
||||
return s
|
||||
}
|
Loading…
x
Reference in New Issue
Block a user