refine backoff

Signed-off-by: husharp <[email protected]>

client/base_client.go

@@ -140,7 +140,7 @@ func (c *baseClient) memberLoop() {
 		case <-c.checkLeaderCh:
 		case <-ticker.C:
 		case <-ctx.Done():
-			log.Info("[pd.reconnectLoop] exit reconnectLoop")
+			log.Info("[pd.memberLoop] exit memberLoop")
 			return
 		}
 		failpoint.Inject("skipUpdateMember", func() {

client/retry/backoff.go

@@ -24,8 +24,9 @@ import (
 
 // BackOffer is a backoff policy for retrying operations.
 type BackOffer struct {
-	maxBackoff  time.Duration
-	nextBackoff time.Duration
+	maxBackoff     time.Duration
+	nextBackoff    time.Duration
+	initialBackoff time.Duration
 }
 
 // WithBackoff is a helper function to add backoff.
@@ -56,18 +57,19 @@ func WithBackoff(
 // InitialBackOffer make the initial state for retrying.
 func InitialBackOffer(initialBackoff, maxBackoff time.Duration) BackOffer {
 	return BackOffer{
-		maxBackoff:  maxBackoff,
-		nextBackoff: initialBackoff,
+		maxBackoff:     maxBackoff,
+		initialBackoff: initialBackoff,
+		nextBackoff:    initialBackoff,
 	}
 }
 
-// NextBackoff implements the `Backoffer`, for now use the `ExponentialBackoff`.
+// NextBackoff for now use the `exponentialBackoff`.
 func (rs *BackOffer) NextBackoff() time.Duration {
-	return rs.ExponentialBackoff()
+	return rs.exponentialBackoff()
 }
 
-// ExponentialBackoff Get the exponential backoff duration.
-func (rs *BackOffer) ExponentialBackoff() time.Duration {
+// exponentialBackoff Get the exponential backoff duration.
+func (rs *BackOffer) exponentialBackoff() time.Duration {
 	backoff := rs.nextBackoff
 	rs.nextBackoff *= 2
 	if rs.nextBackoff > rs.maxBackoff {
@@ -78,7 +80,7 @@ func (rs *BackOffer) ExponentialBackoff() time.Duration {
 
 // ResetBackoff reset the backoff to initial state.
 func (rs *BackOffer) ResetBackoff() {
-	rs.nextBackoff = 0
+	rs.nextBackoff = rs.initialBackoff
 }
 
 // Only used for test.

client/retry/backoff_test.go

@@ -19,6 +19,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/pingcap/errors"
 	"github.com/stretchr/testify/require"
 )
 
@@ -40,8 +41,7 @@ func TestExponentialBackoff(t *testing.T) {
 	// Reset backoff
 	backoff.ResetBackoff()
 	err := WithBackoff(context.Background(), func() error {
-		return nil
+		return errors.New("test")
 	}, &backoff)
-	re.Nil(err)
-
+	re.Error(err)
 }