Exemple #1
0
// requestLeaderLease sends a request to obtain or extend a leader lease for
// this replica. Unless an error is returned, the obtained lease will be valid
// for a time interval containing the requested timestamp.
func (r *Range) requestLeaderLease(timestamp proto.Timestamp) error {
	// TODO(Tobias): get duration from configuration, either as a config flag
	// or, later, dynamically adjusted.
	duration := int64(DefaultLeaderLeaseDuration)
	// Prepare a Raft command to get a leader lease for this replica.
	expiration := timestamp.Add(duration, 0)
	args := &proto.InternalLeaderLeaseRequest{
		RequestHeader: proto.RequestHeader{
			Key:       r.Desc().StartKey,
			Timestamp: timestamp,
			CmdID: proto.ClientCmdID{
				WallTime: r.rm.Clock().Now().WallTime,
				Random:   rand.Int63(),
			},
		},
		Lease: proto.Lease{
			Start:      timestamp,
			Expiration: expiration,
			RaftNodeID: r.rm.RaftNodeID(),
		},
	}
	// Send lease request directly to raft in order to skip unnecessary
	// checks from normal request machinery, (e.g. the command queue).
	errChan, pendingCmd := r.proposeRaftCommand(r.context(), args, &proto.InternalLeaderLeaseResponse{})
	var err error
	if err = <-errChan; err == nil {
		// Next if the command was committed, wait for the range to apply it.
		err = <-pendingCmd.done
	}
	return err
}
Exemple #2
0
// requestLeaderLease sends a request to obtain or extend a leader lease for
// this replica. Unless an error is returned, the obtained lease will be valid
// for a time interval containing the requested timestamp.
func (r *Replica) requestLeaderLease(timestamp proto.Timestamp) error {
	// TODO(Tobias): get duration from configuration, either as a config flag
	// or, later, dynamically adjusted.
	duration := int64(DefaultLeaderLeaseDuration)
	// Prepare a Raft command to get a leader lease for this replica.
	expiration := timestamp.Add(duration, 0)
	desc := r.Desc()
	args := &proto.LeaderLeaseRequest{
		RequestHeader: proto.RequestHeader{
			Key:       desc.StartKey,
			Timestamp: timestamp,
			CmdID: proto.ClientCmdID{
				WallTime: r.rm.Clock().Now().WallTime,
				Random:   rand.Int63(),
			},
			RangeID: desc.RangeID,
		},
		Lease: proto.Lease{
			Start:      timestamp,
			Expiration: expiration,
			RaftNodeID: r.rm.RaftNodeID(),
		},
	}
	// Send lease request directly to raft in order to skip unnecessary
	// checks from normal request machinery, (e.g. the command queue).
	// Note that the command itself isn't traced, but usually the caller
	// waiting for the result has an active Trace.
	errChan, pendingCmd := r.proposeRaftCommand(r.context(), args)
	if err := <-errChan; err != nil {
		return err
	}
	// Next if the command was committed, wait for the range to apply it.
	return (<-pendingCmd.done).Err
}