br: add chaos testing for advancer owner (#58183)

close pingcap/tidb#50458

br/pkg/streamhelper/advancer.go

@@ -90,8 +90,8 @@ func (c *CheckpointAdvancer) HasTask() bool {
 	return c.task != nil
 }
 
-// HasSubscriber returns whether the advancer is associated with a subscriber.
-func (c *CheckpointAdvancer) HasSubscribion() bool {
+// HasSubscriptions returns whether the advancer is associated with a subscriber.
+func (c *CheckpointAdvancer) HasSubscriptions() bool {
 	c.subscriberMu.Lock()
 	defer c.subscriberMu.Unlock()
 
@@ -117,7 +117,7 @@ func newCheckpointWithTS(ts uint64) *checkpoint {
 	}
 }
 
-func NewCheckpointWithSpan(s spans.Valued) *checkpoint {
+func newCheckpointWithSpan(s spans.Valued) *checkpoint {
 	return &checkpoint{
 		StartKey:        s.Key.StartKey,
 		EndKey:          s.Key.EndKey,
@@ -270,11 +270,6 @@ func (c *CheckpointAdvancer) WithCheckpoints(f func(*spans.ValueSortedFull)) {
 	f(c.checkpoints)
 }
 
-// only used for test
-func (c *CheckpointAdvancer) NewCheckpoints(cps *spans.ValueSortedFull) {
-	c.checkpoints = cps
-}
-
 func (c *CheckpointAdvancer) fetchRegionHint(ctx context.Context, startKey []byte) string {
 	region, err := locateKeyOfRegion(ctx, c.env, startKey)
 	if err != nil {
@@ -473,7 +468,7 @@ func (c *CheckpointAdvancer) onTaskEvent(ctx context.Context, e TaskEvent) error
 }
 
 func (c *CheckpointAdvancer) setCheckpoint(s spans.Valued) bool {
-	cp := NewCheckpointWithSpan(s)
+	cp := newCheckpointWithSpan(s)
 	if cp.TS < c.lastCheckpoint.TS {
 		log.Warn("failed to update global checkpoint: stale",
 			zap.Uint64("old", c.lastCheckpoint.TS), zap.Uint64("new", cp.TS))

br/pkg/streamhelper/advancer_test.go

@@ -474,7 +474,7 @@ func TestRemoveTaskAndFlush(t *testing.T) {
 	}, 10*time.Second, 100*time.Millisecond)
 	require.NoError(t, failpoint.Disable("github.com/pingcap/tidb/br/pkg/streamhelper/subscription-handler-loop"))
 	require.Eventually(t, func() bool {
-		return !adv.HasSubscribion()
+		return !adv.HasSubscriptions()
 	}, 10*time.Second, 100*time.Millisecond)
 }
 

br/pkg/streamhelper/config/advancer_conf.go

@@ -11,18 +11,21 @@ import (
 const (
 	flagBackoffTime         = "backoff-time"
 	flagTickInterval        = "tick-interval"
-	flagFullScanDiffTick    = "full-scan-tick"
-	flagAdvancingByCache    = "advancing-by-cache"
 	flagTryAdvanceThreshold = "try-advance-threshold"
 	flagCheckPointLagLimit  = "check-point-lag-limit"
 
-	DefaultConsistencyCheckTick = 5
-	DefaultTryAdvanceThreshold  = 4 * time.Minute
-	DefaultCheckPointLagLimit   = 48 * time.Hour
-	DefaultBackOffTime          = 5 * time.Second
-	DefaultTickInterval         = 12 * time.Second
-	DefaultFullScanTick         = 4
-	DefaultAdvanceByCache       = true
+	// used for chaos testing
+	flagOwnershipCycleInterval = "ownership-cycle-interval"
+)
+
+const (
+	DefaultTryAdvanceThreshold = 4 * time.Minute
+	DefaultCheckPointLagLimit  = 48 * time.Hour
+	DefaultBackOffTime         = 5 * time.Second
+	DefaultTickInterval        = 12 * time.Second
+
+	// used for chaos testing, default to disable
+	DefaultOwnershipCycleInterval = 0
 )
 
 var (
@@ -38,6 +41,11 @@ type Config struct {
 	TryAdvanceThreshold time.Duration `toml:"try-advance-threshold" json:"try-advance-threshold"`
 	// The maximum lag could be tolerated for the checkpoint lag.
 	CheckPointLagLimit time.Duration `toml:"check-point-lag-limit" json:"check-point-lag-limit"`
+
+	// Following configs are used in chaos testings, better not to enable in prod
+	//
+	// used to periodically becomes/retire advancer owner
+	OwnershipCycleInterval time.Duration `toml:"ownership-cycle-interval" json:"ownership-cycle-interval"`
 }
 
 func DefineFlagsForCheckpointAdvancerConfig(f *pflag.FlagSet) {
@@ -49,14 +57,22 @@ func DefineFlagsForCheckpointAdvancerConfig(f *pflag.FlagSet) {
 		"If the checkpoint lag is greater than how long, we would try to poll TiKV for checkpoints.")
 	f.Duration(flagCheckPointLagLimit, DefaultCheckPointLagLimit,
 		"The maximum lag could be tolerated for the checkpoint lag.")
+
+	// used for chaos testing
+	f.Duration(flagOwnershipCycleInterval, DefaultOwnershipCycleInterval,
+		"The interval that the owner will retire itself")
+
+	// mark hidden
+	_ = f.MarkHidden(flagOwnershipCycleInterval)
 }
 
 func Default() Config {
 	return Config{
-		BackoffTime:         DefaultBackOffTime,
-		TickDuration:        DefaultTickInterval,
-		TryAdvanceThreshold: DefaultTryAdvanceThreshold,
-		CheckPointLagLimit:  DefaultCheckPointLagLimit,
+		BackoffTime:            DefaultBackOffTime,
+		TickDuration:           DefaultTickInterval,
+		TryAdvanceThreshold:    DefaultTryAdvanceThreshold,
+		CheckPointLagLimit:     DefaultCheckPointLagLimit,
+		OwnershipCycleInterval: DefaultOwnershipCycleInterval,
 	}
 }
 
@@ -78,6 +94,10 @@ func (conf *Config) GetFromFlags(f *pflag.FlagSet) error {
 	if err != nil {
 		return err
 	}
+	conf.OwnershipCycleInterval, err = f.GetDuration(flagOwnershipCycleInterval)
+	if err != nil {
+		return err
+	}
 	return nil
 }
 

br/pkg/streamhelper/daemon/owner_daemon.go

@@ -102,3 +102,11 @@ func (od *OwnerDaemon) Begin(ctx context.Context) (func(), error) {
 	}
 	return loop, nil
 }
+
+func (od *OwnerDaemon) ForceToBeOwner(ctx context.Context) error {
+	return od.manager.ForceToBeOwner(ctx)
+}
+
+func (od *OwnerDaemon) RetireIfOwner() {
+	od.manager.RetireOwner()
+}

br/pkg/streamhelper/daemon/owner_daemon_test.go

@@ -149,7 +149,6 @@ func TestDaemon(t *testing.T) {
 	ow.RetireOwner()
 	req.False(ow.IsOwner())
 	app.AssertNotRunning(1 * time.Second)
-	ow.CampaignOwner()
 	req.Eventually(func() bool {
 		return ow.IsOwner()
 	}, 1*time.Second, 100*time.Millisecond)

br/pkg/task/stream.go

@@ -919,6 +919,8 @@ func RunStreamResume(
 func RunStreamAdvancer(c context.Context, g glue.Glue, cmdName string, cfg *StreamConfig) error {
 	ctx, cancel := context.WithCancel(c)
 	defer cancel()
+	log.Info("starting", zap.String("cmd", cmdName))
+
 	mgr, err := NewMgr(ctx, g, cfg.PD, cfg.TLS, GetKeepalive(&cfg.Config),
 		cfg.CheckRequirements, false, conn.StreamVersionChecker)
 	if err != nil {
@@ -941,10 +943,46 @@ func RunStreamAdvancer(c context.Context, g glue.Glue, cmdName string, cfg *Stre
 	if err != nil {
 		return err
 	}
+	if cfg.AdvancerCfg.OwnershipCycleInterval > 0 {
+		err = advancerd.ForceToBeOwner(ctx)
+		if err != nil {
+			return err
+		}
+		log.Info("command line advancer forced to be the owner")
+		go runOwnershipCycle(ctx, advancerd, cfg.AdvancerCfg.OwnershipCycleInterval, true)
+	}
 	loop()
 	return nil
 }
 
+// runOwnershipCycle handles the periodic cycling of ownership for the advancer
+func runOwnershipCycle(ctx context.Context, advancerd *daemon.OwnerDaemon, cycleDuration time.Duration, isOwner bool) {
+	ticker := time.NewTicker(cycleDuration)
+	defer ticker.Stop()
+
+	for {
+		select {
+		case <-ctx.Done():
+			return
+		case <-ticker.C:
+			if !isOwner {
+				// try to become owner
+				if err := advancerd.ForceToBeOwner(ctx); err != nil {
+					log.Error("command line advancer failed to force ownership", zap.Error(err))
+					continue
+				}
+				log.Info("command line advancer forced to be the owner")
+				isOwner = true
+			} else {
+				// retire from being owner
+				advancerd.RetireIfOwner()
+				log.Info("command line advancer retired from being owner")
+				isOwner = false
+			}
+		}
+	}
+}
+
 func checkConfigForStatus(pd []string) error {
 	if len(pd) == 0 {
 		return errors.Annotatef(berrors.ErrInvalidArgument,

pkg/config/BUILD.bazel

@@ -11,7 +11,6 @@ go_library(
     importpath = "github.com/pingcap/tidb/pkg/config",
     visibility = ["//visibility:public"],
     deps = [
-        "//br/pkg/streamhelper/config",
         "//pkg/parser/terror",
         "//pkg/util/logutil",
         "//pkg/util/tiflashcompute",

pkg/config/config.go

@@ -33,7 +33,6 @@ import (
 	"github.com/BurntSushi/toml"
 	"github.com/pingcap/errors"
 	zaplog "github.com/pingcap/log"
-	logbackupconf "github.com/pingcap/tidb/br/pkg/streamhelper/config"
 	"github.com/pingcap/tidb/pkg/parser/terror"
 	"github.com/pingcap/tidb/pkg/util/logutil"
 	"github.com/pingcap/tidb/pkg/util/tiflashcompute"
@@ -458,13 +457,6 @@ func (b *AtomicBool) UnmarshalText(text []byte) error {
 	return nil
 }
 
-// LogBackup is the config for log backup service.
-// For now, it includes the embed advancer.
-type LogBackup struct {
-	Advancer logbackupconf.Config `toml:"advancer" json:"advancer"`
-	Enabled  bool                 `toml:"enabled" json:"enabled"`
-}
-
 // Log is the log section of config.
 type Log struct {
 	// Log level.