support config tso switch

Signed-off-by: Ryan Leung <rleungx@gmail.com>

client/pd_service_discovery.go

@@ -575,6 +575,9 @@ func (c *pdServiceDiscovery) updateServiceModeLoop() {
 	ctx, cancel := context.WithCancel(c.ctx)
 	defer cancel()
 	ticker := time.NewTicker(serviceModeUpdateInterval)
+	failpoint.Inject("fastUpdateServiceMode", func() {
+		ticker.Reset(10 * time.Millisecond)
+	})
 	defer ticker.Stop()
 
 	for {

server/cluster/cluster.go

@@ -114,9 +114,6 @@ const (
 	heartbeatTaskRunner = "heartbeat-async"
 	miscTaskRunner      = "misc-async"
 	logTaskRunner       = "log-async"
-
-	// TODO: make it configurable
-	IsTSODynamicSwitchingEnabled = false
 )
 
 // Server is the interface for cluster.
@@ -412,7 +409,7 @@ func (c *RaftCluster) checkSchedulingService() {
 // checkTSOService checks the TSO service.
 func (c *RaftCluster) checkTSOService() {
 	if c.isAPIServiceMode {
-		if IsTSODynamicSwitchingEnabled {
+		if c.opt.GetMicroServiceConfig().IsTSODynamicSwitchingEnabled() {
 			servers, err := discovery.Discover(c.etcdClient, constant.TSOServiceName)
 			if err != nil || len(servers) == 0 {
 				if err := c.startTSOJobsIfNeeded(); err != nil {
@@ -422,7 +419,7 @@ func (c *RaftCluster) checkTSOService() {
 				log.Info("TSO is provided by PD")
 				c.UnsetServiceIndependent(constant.TSOServiceName)
 			} else {
-				if err := c.startTSOJobsIfNeeded(); err != nil {
+				if err := c.stopTSOJobsIfNeeded(); err != nil {
 					log.Error("failed to stop TSO jobs", errs.ZapError(err))
 					return
 				}

server/config/config.go

@@ -854,7 +854,8 @@ func (c *DRAutoSyncReplicationConfig) adjust(meta *configutil.ConfigMetaData) {
 
 // MicroServiceConfig is the configuration for micro service.
 type MicroServiceConfig struct {
-	EnableSchedulingFallback bool `toml:"enable-scheduling-fallback" json:"enable-scheduling-fallback,string"`
+	EnableSchedulingFallback  bool `toml:"enable-scheduling-fallback" json:"enable-scheduling-fallback,string"`
+	EnableTSODynamicSwitching bool `toml:"enable-tso-dynamic-switching" json:"enable-tso-dynamic-switching,string"`
 }
 
 func (c *MicroServiceConfig) adjust(meta *configutil.ConfigMetaData) {
@@ -874,6 +875,11 @@ func (c *MicroServiceConfig) IsSchedulingFallbackEnabled() bool {
 	return c.EnableSchedulingFallback
 }
 
+// IsTSODynamicSwitchingEnabled returns whether to enable TSO dynamic switching.
+func (c *MicroServiceConfig) IsTSODynamicSwitchingEnabled() bool {
+	return c.EnableTSODynamicSwitching
+}
+
 // KeyspaceConfig is the configuration for keyspace management.
 type KeyspaceConfig struct {
 	// PreAlloc contains the keyspace to be allocated during keyspace manager initialization.

server/server.go

@@ -1411,7 +1411,7 @@ func (s *Server) GetRaftCluster() *cluster.RaftCluster {
 // IsServiceIndependent returns whether the service is independent.
 func (s *Server) IsServiceIndependent(name string) bool {
 	if s.mode == APIServiceMode && !s.IsClosed() {
-		if name == constant.TSOServiceName && !cluster.IsTSODynamicSwitchingEnabled {
+		if name == constant.TSOServiceName && !s.GetMicroServiceConfig().IsTSODynamicSwitchingEnabled() {
 			return true
 		}
 		return s.cluster.IsServiceIndependent(name)

tests/integrations/mcs/tso/server_test.go

@@ -40,6 +40,7 @@ import (
 	"github.com/tikv/pd/pkg/utils/tempurl"
 	"github.com/tikv/pd/pkg/utils/testutil"
 	"github.com/tikv/pd/pkg/utils/tsoutil"
+	"github.com/tikv/pd/server/config"
 	"github.com/tikv/pd/tests"
 	"github.com/tikv/pd/tests/integrations/mcs"
 	clientv3 "go.etcd.io/etcd/client/v3"
@@ -575,3 +576,95 @@ func (suite *CommonTestSuite) TestBootstrapDefaultKeyspaceGroup() {
 	suite.pdLeader.ResignLeader()
 	suite.pdLeader = suite.cluster.GetServer(suite.cluster.WaitLeader())
 }
+
+// TestTSOServiceSwitch tests the behavior of TSO service switching when `EnableTSODynamicSwitching` is enabled.
+// Initially, the TSO service should be provided by PD. After starting a TSO server, the service should switch to the TSO server.
+// When the TSO server is stopped, the PD should resume providing the TSO service if `EnableTSODynamicSwitching` is enabled.
+// If `EnableTSODynamicSwitching` is disabled, the PD should not provide TSO service after the TSO server is stopped.
+func TestTSOServiceSwitch(t *testing.T) {
+	re := require.New(t)
+	re.NoError(failpoint.Enable("github.com/tikv/pd/client/fastUpdateServiceMode", `return(true)`))
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	tc, err := tests.NewTestAPICluster(ctx, 1,
+		func(conf *config.Config, _ string) {
+			conf.MicroService.EnableTSODynamicSwitching = true
+		},
+	)
+	re.NoError(err)
+	defer tc.Destroy()
+
+	err = tc.RunInitialServers()
+	re.NoError(err)
+	leaderName := tc.WaitLeader()
+	re.NotEmpty(leaderName)
+	pdLeader := tc.GetServer(leaderName)
+	backendEndpoints := pdLeader.GetAddr()
+	re.NoError(pdLeader.BootstrapCluster())
+	pdClient, err := pd.NewClientWithContext(ctx, []string{backendEndpoints}, pd.SecurityOption{})
+	re.NoError(err)
+	re.NotNil(pdClient)
+	defer pdClient.Close()
+
+	var globalLastTS uint64
+	// Initially, TSO service should be provided by PD
+	re.NoError(checkTSOMonotonic(ctx, pdClient, &globalLastTS, 10))
+
+	// Start TSO server
+	tsoCluster, err := tests.NewTestTSOCluster(ctx, 1, pdLeader.GetAddr())
+	re.NoError(err)
+	tsoCluster.WaitForDefaultPrimaryServing(re)
+
+	// Wait for TSO server to start and PD to detect it
+	time.Sleep(300 * time.Millisecond)
+
+	// Verify PD is not providing TSO service
+	err = checkTSOMonotonic(ctx, pdClient, &globalLastTS, 10)
+	re.NoError(err)
+
+	// Disable TSO switching
+	cfg := pdLeader.GetServer().GetMicroServiceConfig().Clone()
+	cfg.EnableTSODynamicSwitching = false
+	pdLeader.GetServer().SetMicroServiceConfig(*cfg)
+
+	tsoCluster.Destroy()
+
+	// Wait for the configuration change to take effect
+	time.Sleep(300 * time.Millisecond)
+	// Verify PD is not providing TSO service multiple times
+	for i := 0; i < 10; i++ {
+		err = checkTSOMonotonic(ctx, pdClient, &globalLastTS, 1)
+		re.Error(err, "TSO service should not be available")
+		time.Sleep(10 * time.Millisecond)
+	}
+
+	// Now enable TSO switching
+	cfg = pdLeader.GetServer().GetMicroServiceConfig().Clone()
+
+	cfg.EnableTSODynamicSwitching = true
+	pdLeader.GetServer().SetMicroServiceConfig(*cfg)
+
+	// Wait for PD to detect the change
+	time.Sleep(300 * time.Millisecond)
+
+	// Verify PD is now providing TSO service and timestamps are monotonically increasing
+	re.NoError(checkTSOMonotonic(ctx, pdClient, &globalLastTS, 10))
+	re.NoError(failpoint.Disable("github.com/tikv/pd/client/fastUpdateServiceMode"))
+}
+
+func checkTSOMonotonic(ctx context.Context, pdClient pd.Client, globalLastTS *uint64, count int) error {
+	fmt.Println("start to request TSO")
+	for i := 0; i < count; i++ {
+		physical, logical, err := pdClient.GetTS(ctx)
+		if err != nil {
+			return err
+		}
+		ts := (uint64(physical) << 18) + uint64(logical)
+		if ts <= *globalLastTS {
+			return fmt.Errorf("TSO is not globally increasing: last %d, current %d", globalLastTS, ts)
+		}
+		*globalLastTS = ts
+	}
+	return nil
+}