func (r *Replica) HandleQLeaseReply(ql *qlease.Lease, pr *qleaseproto.PromiseReply) {
if pr.TimestampNs < ql.LatestTsSent {
//old reply, ignore
return
}
if pr.LeaseInstance > ql.PromisedByMeInst {
ql.PromiseRejects++
if ql.PromiseRejects == r.N {
ql.WriteInQuorumUntil = 0
}
return
}
now := time.Now().UnixNano()
max := now
for i := int32(0); i < int32(r.N); i++ {
if i == r.Id {
continue
}
if i == pr.ReplicaId {
ql.LatestRepliesReceived[i] = now + ql.Duration
}
if max < ql.LatestRepliesReceived[i] {
max = ql.LatestRepliesReceived[i]
}
}
ql.WriteInQuorumUntil = max
r.LastReplyReceivedTimestamp[pr.ReplicaId] = now
}
func (r *Replica) EstablishQLease(ql *qlease.Lease) {
now := time.Now().UnixNano()
ql.LatestTsSent = now
ql.PromiseRejects = 0
g := &qleaseproto.Guard{r.Id, now, qlease.GUARD_DURATION_NS}
for i := int32(0); i < int32(r.N); i++ {
if i == r.Id || !r.Alive[i] {
continue
}
r.SendMsg(i, r.qleaseGuardRPC, g)
}
}
func (r *Replica) RenewQLease(ql *qlease.Lease, latestAccInst int32) {
now := time.Now().UnixNano()
ql.PromiseRejects = 0
p := &qleaseproto.Promise{r.Id, ql.PromisedByMeInst, now, ql.Duration, latestAccInst}
for i := int32(0); i < int32(r.N); i++ {
if i == r.Id || !r.Alive[i] {
continue
}
ql.LatestRepliesReceived[i] += ql.Duration
r.SendMsg(i, r.qleasePromiseRPC, p)
}
ql.LatestTsSent = now
// sufficient to extend wait time by the duration of the lease, because
// grantees must receive the lease refresh message before the previous lease expires
// (otherwise they will dicount the refresh)
ql.WriteInQuorumUntil += ql.Duration
}
func (r *Replica) HandleQLeasePromise(ql *qlease.Lease, p *qleaseproto.Promise) bool {
now := time.Now().UnixNano()
// check that this promise was received on time
if ql.LatestPromisesReceived[p.ReplicaId] < now && ql.GuardExpires[p.ReplicaId] < now {
//didn't receive promise on time, must ignore
//TODO: send NACK as optimization
return false
}
if p.LeaseInstance < ql.PromisedToMeInst {
// the sender must update its lease view
pr := &qleaseproto.PromiseReply{r.Id, ql.PromisedToMeInst, p.TimestampNs}
r.SendMsg(p.ReplicaId, r.qleasePromiseReplyRPC, pr)
return false
} else if p.LeaseInstance > ql.PromisedToMeInst {
ql.PromisedToMeInst = p.LeaseInstance
for i := int32(0); i < int32(r.N); i++ {
ql.LatestPromisesReceived[i] = 0
}
}
ql.LatestPromisesReceived[p.ReplicaId] = now + p.DurationNs
//send reply
pr := &qleaseproto.PromiseReply{r.Id, ql.PromisedToMeInst, p.TimestampNs}
r.SendMsg(p.ReplicaId, r.qleasePromiseReplyRPC, pr)
sorted := make([]int64, r.N)
copy(sorted, ql.LatestPromisesReceived)
sorted[r.Id] = 0
sort.Sort(Int64Slice(sorted))
ql.ReadLocallyUntil = sorted[r.N-(r.N/2)]
return true
}
func (r *Replica) HandleQLeaseGuardReply(ql *qlease.Lease, gr *qleaseproto.GuardReply, latestAccInst int32) {
if gr.TimestampNs < ql.LatestTsSent {
//old reply, must ignore
return
}
now := time.Now().UnixNano()
p := &qleaseproto.Promise{r.Id, ql.PromisedByMeInst, now, ql.Duration, latestAccInst}
ql.LatestRepliesReceived[gr.ReplicaId] = now + qlease.GUARD_DURATION_NS + ql.Duration
if ql.WriteInQuorumUntil < ql.LatestRepliesReceived[gr.ReplicaId] {
ql.WriteInQuorumUntil = ql.LatestRepliesReceived[gr.ReplicaId]
}
r.SendMsg(gr.ReplicaId, r.qleasePromiseRPC, p)
}