use internal/backoff

balancer/grpclb/grpclb.go

@@ -37,6 +37,7 @@ import (
 	lbpb "google.golang.org/grpc/balancer/grpclb/grpc_lb_v1"
 	"google.golang.org/grpc/connectivity"
 	"google.golang.org/grpc/grpclog"
+	"google.golang.org/grpc/internal/backoff"
 	"google.golang.org/grpc/resolver"
 )
 
@@ -46,6 +47,19 @@ const (
 	grpclbName             = "grpclb"
 )
 
+var (
+	// defaultBackoffConfig configures the backoff strategy that's used when the
+	// init handshake in the RPC is unsuccessful. It's not for the clientconn
+	// reconnect backoff.
+	//
+	// It has the same value as the default grpc.DefaultBackoffConfig.
+	//
+	// TODO: make backoff configurable.
+	defaultBackoffConfig = backoff.Exponential{
+		MaxDelay: 120 * time.Second,
+	}
+)
+
 func convertDuration(d *durationpb.Duration) time.Duration {
 	if d == nil {
 		return 0
@@ -147,7 +161,7 @@ func (b *lbBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) bal
 		scStates:       make(map[balancer.SubConn]connectivity.State),
 		picker:         &errPicker{err: balancer.ErrNoSubConnAvailable},
 		clientStats:    newRPCStats(),
-		backoff:        grpc.DefaultBackoffConfig, // TODO: make backoff configurable
+		backoff:        defaultBackoffConfig, // TODO: make backoff configurable.
 	}
 
 	return lb
@@ -167,7 +181,7 @@ type lbBalancer struct {
 	// The ClientConn to talk to the remote balancer.
 	ccRemoteLB *grpc.ClientConn
 	// backoff for calling remote balancer.
-	backoff grpc.BackoffConfig
+	backoff backoff.Strategy
 
 	// Support client side load reporting. Each picker gets a reference to this,
 	// and will update its content.

balancer/grpclb/grpclb_remote_balancer.go

@@ -238,7 +238,7 @@ func (lb *lbBalancer) watchRemoteBalancer() {
 			continue
 		}
 
-		timer := time.NewTimer(lb.backoff.backoff(retryCount))
+		timer := time.NewTimer(lb.backoff.Backoff(retryCount))
 		select {
 		case <-timer.C:
 		case <-lb.doneCh: