fix

Signed-off-by: husharp <jinhao.hu@pingcap.com>

integration_tests/pd_api_test.go

@@ -37,6 +37,7 @@ package tikv_test
 import (
 	"context"
 	"fmt"
+	"math"
 	"strings"
 	"sync/atomic"
 	"testing"
@@ -208,6 +209,55 @@ func (s *apiTestSuite) TestDCLabelClusterMinResolvedTS() {
 	require.Equal(uint64(150), s.store.GetMinSafeTS(dcLabel))
 }
 
+func (s *apiTestSuite) TestInitClusterMinResolvedTSZero() {
+	util.EnableFailpoints()
+	require := s.Require()
+	require.NoError(failpoint.Enable("tikvclient/mockFastSafeTSUpdater", `return()`))
+	defer func() {
+		require.NoError(failpoint.Disable("tikvclient/mockFastSafeTSUpdater"))
+	}()
+	// Try to get the minimum resolved timestamp of the cluster from PD.
+	require.NoError(failpoint.Enable("tikvclient/InjectMinResolvedTS", `return(100)`))
+	mockClient := storeSafeTsMockClient{
+		Client: s.store.GetTiKVClient(),
+	}
+	s.store.SetTiKVClient(&mockClient)
+	// Mock safeTS is not initialized.
+	s.store.SetStoreSafeTS(uint64(1), 0)
+	s.store.SetMinSafeTS(oracle.GlobalTxnScope, 0)
+	require.Equal(uint64(0), s.store.GetMinSafeTS(oracle.GlobalTxnScope))
+
+	var retryCount int
+	for s.store.GetMinSafeTS(oracle.GlobalTxnScope) != 100 {
+		require.NotEqual(uint64(math.MaxUint64), s.store.GetMinSafeTS(oracle.GlobalTxnScope))
+		time.Sleep(100 * time.Millisecond)
+		if retryCount > 5 {
+			break
+		}
+		retryCount++
+	}
+	require.Equal(uint64(100), s.store.GetMinSafeTS(oracle.GlobalTxnScope))
+	require.NoError(failpoint.Disable("tikvclient/InjectMinResolvedTS"))
+
+	// Try to get the minimum resolved timestamp of the cluster from TiKV.
+	require.NoError(failpoint.Enable("tikvclient/InjectMinResolvedTS", `return(0)`))
+	// Mock safeTS is not initialized.
+	s.store.SetStoreSafeTS(uint64(1), 0)
+	s.store.SetMinSafeTS(oracle.GlobalTxnScope, 0)
+	require.Equal(uint64(0), s.store.GetMinSafeTS(oracle.GlobalTxnScope))
+
+	for s.store.GetMinSafeTS(oracle.GlobalTxnScope) != 150 {
+		require.NotEqual(uint64(math.MaxUint64), s.store.GetMinSafeTS(oracle.GlobalTxnScope))
+		time.Sleep(100 * time.Millisecond)
+		if retryCount > 5 {
+			break
+		}
+		retryCount++
+	}
+	require.Equal(uint64(150), s.store.GetMinSafeTS(oracle.GlobalTxnScope))
+	require.NoError(failpoint.Disable("tikvclient/InjectMinResolvedTS"))
+}
+
 func (s *apiTestSuite) TearDownTest() {
 	if s.store != nil {
 		s.Require().Nil(s.store.Close())

tikv/kv.go

@@ -500,6 +500,9 @@ func (s *KVStore) GetTiKVClient() (client Client) {
 // GetMinSafeTS return the minimal safeTS of the storage with given txnScope.
 func (s *KVStore) GetMinSafeTS(txnScope string) uint64 {
 	if val, ok := s.minSafeTS.Load(txnScope); ok {
+		if val.(uint64) == uint64(math.MaxUint64) {
+			return 0
+		}
 		return val.(uint64)
 	}
 	return 0
@@ -850,3 +853,15 @@ type SchemaVer = transaction.SchemaVer
 // MaxTxnTimeUse is the max time a Txn may use (in ms) from its begin to commit.
 // We use it to abort the transaction to guarantee GC worker will not influence it.
 const MaxTxnTimeUse = transaction.MaxTxnTimeUse
+
+// SetMinSafeTS set the minimal safeTS of the storage with given txnScope.
+// Note: it is only used for test.
+func (s *KVStore) SetMinSafeTS(txnScope string, safeTS uint64) {
+	s.minSafeTS.Store(txnScope, safeTS)
+}
+
+// SetStoreSafeTS set the safeTS of the store with given storeID.
+// Note: it is only used for test.
+func (s *KVStore) SetStoreSafeTS(storeID, safeTS uint64) {
+	s.safeTSMap.Store(storeID, safeTS)
+}