puller(ticdc): detect resolved ts stuck in puller (#10182) (#10221)

close #10181
pingcap · Dec 7, 2023 · 6b4b212 · 6b4b212
1 parent 0050e31
commit 6b4b212
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Showing 5 changed files with 71 additions and 3 deletions.
diff --git a/cdc/puller/puller.go b/cdc/puller/puller.go
@@ -71,6 +71,10 @@ type pullerImpl struct {
 	changefeed model.ChangeFeedID
 	tableID    model.TableID
 	tableName  string
+
+	cfg                   *config.ServerConfig
+	lastForwardTime       time.Time
+	lastForwardResolvedTs uint64
 }
 
 // New create a new Puller fetch event start from checkpointTs and put into buf.
@@ -110,6 +114,7 @@ func New(ctx context.Context,
 		changefeed:   changefeed,
 		tableID:      tableID,
 		tableName:    tableName,
+		cfg:          cfg,
 	}
 	return p
 }
@@ -138,8 +143,8 @@ func (p *pullerImpl) Run(ctx context.Context) error {
 
 	lastResolvedTs := p.checkpointTs
 	g.Go(func() error {
-		metricsTicker := time.NewTicker(15 * time.Second)
-		defer metricsTicker.Stop()
+		stuckDetectorTicker := time.NewTicker(1 * time.Minute)
+		defer stuckDetectorTicker.Stop()
 		output := func(raw *model.RawKVEntry) error {
 			// even after https://github.com/pingcap/tiflow/pull/2038, kv client
 			// could still miss region change notification, which leads to resolved
@@ -176,6 +181,11 @@ func (p *pullerImpl) Run(ctx context.Context) error {
 			select {
 			case <-ctx.Done():
 				return errors.Trace(ctx.Err())
+			case <-stuckDetectorTicker.C:
+				if err := p.detectResolvedTsStuck(initialized); err != nil {
+					return errors.Trace(err)
+				}
+				continue
 			case e = <-eventCh:
 			}
 
@@ -235,6 +245,29 @@ func (p *pullerImpl) Run(ctx context.Context) error {
 	return g.Wait()
 }
 
+func (p *pullerImpl) detectResolvedTsStuck(initialized bool) error {
+	if p.cfg.Debug.Puller.EnableResolvedTsStuckDetection && initialized {
+		resolvedTs := p.tsTracker.Frontier()
+		if resolvedTs == p.lastForwardResolvedTs {
+			log.Warn("ResolvedTs stuck detected in puller",
+				zap.String("namespace", p.changefeed.Namespace),
+				zap.String("changefeed", p.changefeed.ID),
+				zap.Int64("tableID", p.tableID),
+				zap.String("tableName", p.tableName),
+				zap.Uint64("lastResolvedTs", p.lastForwardResolvedTs),
+				zap.Uint64("resolvedTs", resolvedTs))
+			if time.Since(p.lastForwardTime) > time.Duration(p.cfg.Debug.Puller.ResolvedTsStuckInterval) {
+				// throw an error to cause changefeed restart
+				return errors.New("resolved ts stuck")
+			}
+		} else {
+			p.lastForwardTime = time.Now()
+			p.lastForwardResolvedTs = resolvedTs
+		}
+	}
+	return nil
+}
+
 func (p *pullerImpl) Output() <-chan *model.RawKVEntry {
 	return p.outputCh
 }

diff --git a/pkg/cmd/server/server_test.go b/pkg/cmd/server/server_test.go
@@ -199,6 +199,10 @@ func TestParseCfg(t *testing.T) {
 				CheckBalanceInterval: 60000000000,
 				AddTableBatchSize:    50,
 			},
+			Puller: &config.PullerConfig{
+				EnableResolvedTsStuckDetection: false,
+				ResolvedTsStuckInterval:        config.TomlDuration(5 * time.Minute),
+			},
 		},
 		ClusterID:           "default",
 		MaxMemoryPercentage: config.DisableMemoryLimit,
@@ -338,6 +342,10 @@ check-balance-interval = "10s"
 				CheckBalanceInterval: config.TomlDuration(10 * time.Second),
 				AddTableBatchSize:    50,
 			},
+			Puller: &config.PullerConfig{
+				EnableResolvedTsStuckDetection: false,
+				ResolvedTsStuckInterval:        config.TomlDuration(5 * time.Minute),
+			},
 		},
 		ClusterID:           "default",
 		MaxMemoryPercentage: config.DisableMemoryLimit,
@@ -469,6 +477,10 @@ cert-allowed-cn = ["dd","ee"]
 				CheckBalanceInterval: 60000000000,
 				AddTableBatchSize:    50,
 			},
+			Puller: &config.PullerConfig{
+				EnableResolvedTsStuckDetection: false,
+				ResolvedTsStuckInterval:        config.TomlDuration(5 * time.Minute),
+			},
 		},
 		ClusterID:           "default",
 		MaxMemoryPercentage: config.DisableMemoryLimit,
@@ -527,5 +539,9 @@ unknown3 = 3
 			CheckBalanceInterval: 60000000000,
 			AddTableBatchSize:    50,
 		},
+		Puller: &config.PullerConfig{
+			EnableResolvedTsStuckDetection: false,
+			ResolvedTsStuckInterval:        config.TomlDuration(5 * time.Minute),
+		},
 	}, o.serverConfig.Debug)
 }
diff --git a/pkg/config/config_test_data.go b/pkg/config/config_test_data.go
@@ -161,7 +161,11 @@ const (
       "check-balance-interval": 60000000000,
       "add-table-batch-size": 50
     },
-    "enable-kv-connect-backoff": false
+    "enable-kv-connect-backoff": false,
+    "puller": {
+      "enable-resolved-ts-stuck-detection": false,
+      "resolved-ts-stuck-interval": 300000000000
+    }
   },
   "cluster-id": "default",
   "max-memory-percentage": 0,

diff --git a/pkg/config/debug.go b/pkg/config/debug.go
@@ -28,6 +28,9 @@ type DebugConfig struct {
 
 	// EnableKVConnectBackOff enables the backoff for kv connect.
 	EnableKVConnectBackOff bool `toml:"enable-kv-connect-backoff" json:"enable-kv-connect-backoff"`
+
+	// Puller is the configuration of the puller.
+	Puller *PullerConfig `toml:"puller" json:"puller"`
 }
 
 // ValidateAndAdjust validates and adjusts the debug configuration
@@ -44,3 +47,11 @@ func (c *DebugConfig) ValidateAndAdjust() error {
 
 	return nil
 }
+
+// PullerConfig represents config for puller
+type PullerConfig struct {
+	// EnableResolvedTsStuckDetection is used to enable resolved ts stuck detection.
+	EnableResolvedTsStuckDetection bool `toml:"enable-resolved-ts-stuck-detection" json:"enable-resolved-ts-stuck-detection"`
+	// ResolvedTsStuckInterval is the interval of checking resolved ts stuck.
+	ResolvedTsStuckInterval TomlDuration `toml:"resolved-ts-stuck-interval" json:"resolved-ts-stuck-interval"`
+}
diff --git a/pkg/config/server_config.go b/pkg/config/server_config.go
@@ -134,6 +134,10 @@ var defaultServerConfig = &ServerConfig{
 
 		Scheduler:              NewDefaultSchedulerConfig(),
 		EnableKVConnectBackOff: false,
+		Puller: &PullerConfig{
+			EnableResolvedTsStuckDetection: false,
+			ResolvedTsStuckInterval:        TomlDuration(5 * time.Minute),
+		},
 	},
 	ClusterID:              "default",
 	GcTunerMemoryThreshold: DisableMemoryLimit,