enhance: add broadcast operation for msgstream (#39040)

issue: #38399

- make broadcast service available for msgstream by reusing the
architecture streaming service

---------

Signed-off-by: chyezh <chyezh@outlook.com>

cmd/roles/roles.go

@@ -43,7 +43,6 @@ import (
 	kvfactory "github.com/milvus-io/milvus/internal/util/dependency/kv"
 	"github.com/milvus-io/milvus/internal/util/initcore"
 	internalmetrics "github.com/milvus-io/milvus/internal/util/metrics"
-	"github.com/milvus-io/milvus/internal/util/streamingutil"
 	"github.com/milvus-io/milvus/pkg/config"
 	"github.com/milvus-io/milvus/pkg/log"
 	"github.com/milvus-io/milvus/pkg/metrics"
@@ -389,10 +388,8 @@ func (mr *MilvusRoles) Run() {
 	tracer.Init()
 
 	// Initialize streaming service if enabled.
-	if streamingutil.IsStreamingServiceEnabled() {
-		streaming.Init()
-		defer streaming.Release()
-	}
+	streaming.Init()
+	defer streaming.Release()
 
 	coordclient.EnableLocalClientRole(&coordclient.LocalClientRoleConfig{
 		ServerType:       mr.ServerType,

configs/milvus.yaml

@@ -1121,6 +1121,8 @@ streaming:
     # It's ok to set it into duration string, such as 30s or 1m30s, see time.ParseDuration
     backoffInitialInterval: 50ms
     backoffMultiplier: 2 # The multiplier of balance task trigger backoff, 2 by default
+  walBroadcaster:
+    concurrencyRatio: 1 # The concurrency ratio based on number of CPU for wal broadcaster, 1 by default.
   txn:
     defaultKeepaliveTimeout: 10s # The default keepalive timeout for wal txn, 10s by default
 

internal/distributed/streaming/streaming.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"time"
 
+	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster/registry"
 	kvfactory "github.com/milvus-io/milvus/internal/util/dependency/kv"
 	"github.com/milvus-io/milvus/pkg/streaming/util/message"
 	"github.com/milvus-io/milvus/pkg/streaming/util/options"
@@ -17,6 +18,8 @@ var singleton WALAccesser = nil
 func Init() {
 	c, _ := kvfactory.GetEtcdAndPath()
 	singleton = newWALAccesser(c)
+	// Add the wal accesser to the broadcaster registry for making broadcast operation.
+	registry.Register(registry.AppendOperatorTypeStreaming, singleton)
 }
 
 // Release releases the resources of the wal accesser.

internal/distributed/streaming/streaming_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/milvus-io/milvus-proto/go-api/v2/commonpb"
 	"github.com/milvus-io/milvus-proto/go-api/v2/msgpb"
 	"github.com/milvus-io/milvus/internal/distributed/streaming"
 	"github.com/milvus-io/milvus/pkg/streaming/util/message"
@@ -34,6 +35,10 @@ func TestStreamingProduce(t *testing.T) {
 			PartitionIds: []int64{1, 2, 3},
 		}).
 		WithBody(&msgpb.CreateCollectionRequest{
+			Base: &commonpb.MsgBase{
+				MsgType:   commonpb.MsgType_CreateCollection,
+				Timestamp: 1,
+			},
 			CollectionID: 1,
 		}).
 		WithBroadcast(vChannels).

internal/distributed/streaming/util.go

@@ -8,6 +8,11 @@ import (
 	"github.com/milvus-io/milvus/pkg/streaming/util/types"
 )
 
+type (
+	AppendResponses = types.AppendResponses
+	AppendResponse  = types.AppendResponse
+)
+
 // AppendMessagesToWAL appends messages to the wal.
 // It it a helper utility function to append messages to the wal.
 // If the messages is belong to one vchannel, it will be sent as a transaction.
@@ -26,7 +31,7 @@ func (u *walAccesserImpl) AppendMessages(ctx context.Context, msgs ...message.Mu
 
 	// Otherwise append the messages concurrently.
 	mu := &sync.Mutex{}
-	resp := newAppendResponseN(len(msgs))
+	resp := types.NewAppendResponseN(len(msgs))
 
 	wg := &sync.WaitGroup{}
 	wg.Add(len(dispatchedMessages))
@@ -39,7 +44,7 @@ func (u *walAccesserImpl) AppendMessages(ctx context.Context, msgs ...message.Mu
 			singleResp := u.appendToVChannel(ctx, vchannel, msgs...)
 			mu.Lock()
 			for i, idx := range idxes {
-				resp.fillResponseAtIdx(singleResp.Responses[i], idx)
+				resp.FillResponseAtIdx(singleResp.Responses[i], idx)
 			}
 			mu.Unlock()
 			return struct{}{}, nil
@@ -76,9 +81,9 @@ func (u *walAccesserImpl) dispatchMessages(msgs ...message.MutableMessage) (map[
 // appendToVChannel appends the messages to the specified vchannel.
 func (u *walAccesserImpl) appendToVChannel(ctx context.Context, vchannel string, msgs ...message.MutableMessage) AppendResponses {
 	if len(msgs) == 0 {
-		return newAppendResponseN(0)
+		return types.NewAppendResponseN(0)
 	}
-	resp := newAppendResponseN(len(msgs))
+	resp := types.NewAppendResponseN(len(msgs))
 
 	// if only one message here, append it directly, no more goroutine needed.
 	// at most time, there's only one message here.
@@ -86,7 +91,7 @@ func (u *walAccesserImpl) appendToVChannel(ctx context.Context, vchannel string,
 	// we should optimize the message-format, make it into one; but not the goroutine count.
 	if len(msgs) == 1 {
 		appendResult, err := u.appendToWAL(ctx, msgs[0])
-		resp.fillResponseAtIdx(AppendResponse{
+		resp.FillResponseAtIdx(AppendResponse{
 			AppendResult: appendResult,
 			Error:        err,
 		}, 0)
@@ -99,7 +104,7 @@ func (u *walAccesserImpl) appendToVChannel(ctx context.Context, vchannel string,
 		VChannel: vchannel,
 	})
 	if err != nil {
-		resp.fillAllError(err)
+		resp.FillAllError(err)
 		return resp
 	}
 
@@ -115,7 +120,7 @@ func (u *walAccesserImpl) appendToVChannel(ctx context.Context, vchannel string,
 			defer wg.Done()
 			if err := txn.Append(ctx, msg); err != nil {
 				mu.Lock()
-				resp.fillResponseAtIdx(AppendResponse{
+				resp.FillResponseAtIdx(AppendResponse{
 					Error: err,
 				}, i)
 				mu.Unlock()
@@ -129,75 +134,19 @@ func (u *walAccesserImpl) appendToVChannel(ctx context.Context, vchannel string,
 	// and fill the error with the first error.
 	if err := resp.UnwrapFirstError(); err != nil {
 		_ = txn.Rollback(ctx) // rollback failure can be ignored.
-		resp.fillAllError(err)
+		resp.FillAllError(err)
 		return resp
 	}
 
 	// commit the transaction and fill the response.
 	appendResult, err := txn.Commit(ctx)
-	resp.fillAllResponse(AppendResponse{
+	resp.FillAllResponse(AppendResponse{
 		AppendResult: appendResult,
 		Error:        err,
 	})
 	return resp
 }
 
-// newAppendResponseN creates a new append response.
-func newAppendResponseN(n int) AppendResponses {
-	return AppendResponses{
-		Responses: make([]AppendResponse, n),
-	}
-}
-
-// AppendResponse is the response of one append operation.
-type AppendResponse struct {
-	AppendResult *types.AppendResult
-	Error        error
-}
-
-// AppendResponses is the response of append operation.
-type AppendResponses struct {
-	Responses []AppendResponse
-}
-
-func (a AppendResponses) MaxTimeTick() uint64 {
-	var maxTimeTick uint64
-	for _, r := range a.Responses {
-		if r.AppendResult != nil && r.AppendResult.TimeTick > maxTimeTick {
-			maxTimeTick = r.AppendResult.TimeTick
-		}
-	}
-	return maxTimeTick
-}
-
-// UnwrapFirstError returns the first error in the responses.
-func (a AppendResponses) UnwrapFirstError() error {
-	for _, r := range a.Responses {
-		if r.Error != nil {
-			return r.Error
-		}
-	}
-	return nil
-}
-
-// fillAllError fills all the responses with the same error.
-func (a *AppendResponses) fillAllError(err error) {
-	for i := range a.Responses {
-		a.Responses[i].Error = err
-	}
-}
-
-// fillResponseAtIdx fill the response at idx
-func (a *AppendResponses) fillResponseAtIdx(resp AppendResponse, idx int) {
-	a.Responses[idx] = resp
-}
-
-func (a *AppendResponses) fillAllResponse(resp AppendResponse) {
-	for i := range a.Responses {
-		a.Responses[i] = resp
-	}
-}
-
 // applyOpt applies the append options to the message.
 func applyOpt(msg message.MutableMessage, opts ...AppendOption) message.MutableMessage {
 	if len(opts) == 0 {

internal/distributed/streaming/wal.go

@@ -11,6 +11,7 @@ import (
 	"github.com/milvus-io/milvus/internal/distributed/streaming/internal/producer"
 	"github.com/milvus-io/milvus/internal/streamingcoord/client"
 	"github.com/milvus-io/milvus/internal/streamingnode/client/handler"
+	"github.com/milvus-io/milvus/internal/util/streamingutil"
 	"github.com/milvus-io/milvus/internal/util/streamingutil/status"
 	"github.com/milvus-io/milvus/internal/util/streamingutil/util"
 	"github.com/milvus-io/milvus/pkg/streaming/util/message"
@@ -27,7 +28,11 @@ func newWALAccesser(c *clientv3.Client) *walAccesserImpl {
 	// Create a new streaming coord client.
 	streamingCoordClient := client.NewClient(c)
 	// Create a new streamingnode handler client.
-	handlerClient := handler.NewHandlerClient(streamingCoordClient.Assignment())
+	var handlerClient handler.HandlerClient
+	if streamingutil.IsStreamingServiceEnabled() {
+		// streaming service is enabled, create the handler client for the streaming service.
+		handlerClient = handler.NewHandlerClient(streamingCoordClient.Assignment())
+	}
 	return &walAccesserImpl{
 		lifetime:             typeutil.NewLifetime(),
 		streamingCoordClient: streamingCoordClient,

internal/rootcoord/broadcast_task.go

@@ -0,0 +1,105 @@
+package rootcoord
+
+import (
+	"context"
+
+	"github.com/milvus-io/milvus/internal/util/streamingutil/util"
+	"github.com/milvus-io/milvus/pkg/mq/msgstream"
+	"github.com/milvus-io/milvus/pkg/streaming/util/message"
+	"github.com/milvus-io/milvus/pkg/streaming/util/message/adaptor"
+	"github.com/milvus-io/milvus/pkg/streaming/util/types"
+	"github.com/milvus-io/milvus/pkg/util/funcutil"
+	"github.com/milvus-io/milvus/pkg/util/syncutil"
+)
+
+var _ task = (*broadcastTask)(nil)
+
+// newBroadcastTask creates a new broadcast task.
+func newBroadcastTask(ctx context.Context, core *Core, msgs []message.MutableMessage) *broadcastTask {
+	return &broadcastTask{
+		baseTask: newBaseTask(ctx, core),
+		msgs:     msgs,
+	}
+}
+
+// BroadcastTask is used to implement the broadcast operation based on the msgstream
+// by using the streaming service interface.
+// msgstream will be deprecated since 2.6.0 with streaming service, so those code will be removed in the future version.
+type broadcastTask struct {
+	baseTask
+	msgs         []message.MutableMessage // The message wait for broadcast
+	walName      string
+	resultFuture *syncutil.Future[types.AppendResponses]
+}
+
+func (b *broadcastTask) Execute(ctx context.Context) error {
+	result := types.NewAppendResponseN(len(b.msgs))
+	defer func() {
+		b.resultFuture.Set(result)
+	}()
+
+	for idx, msg := range b.msgs {
+		tsMsg, err := adaptor.NewMsgPackFromMutableMessageV1(msg)
+		if err != nil {
+			result.FillResponseAtIdx(types.AppendResponse{Error: err}, idx)
+			return err
+		}
+		pchannel := funcutil.ToPhysicalChannel(msg.VChannel())
+		msgID, err := b.core.chanTimeTick.broadcastMarkDmlChannels([]string{pchannel}, &msgstream.MsgPack{
+			BeginTs: b.ts,
+			EndTs:   b.ts,
+			Msgs:    []msgstream.TsMsg{tsMsg},
+		})
+		if err != nil {
+			result.FillResponseAtIdx(types.AppendResponse{Error: err}, idx)
+			continue
+		}
+		result.FillResponseAtIdx(types.AppendResponse{
+			AppendResult: &types.AppendResult{
+				MessageID: adaptor.MustGetMessageIDFromMQWrapperIDBytes(b.walName, msgID[pchannel]),
+				TimeTick:  b.ts,
+			},
+		}, idx)
+	}
+	return result.UnwrapFirstError()
+}
+
+func newMsgStreamAppendOperator(c *Core) *msgstreamAppendOperator {
+	return &msgstreamAppendOperator{
+		core:    c,
+		walName: util.MustSelectWALName(),
+	}
+}
+
+// msgstreamAppendOperator the code of streamingcoord to make broadcast available on the legacy msgstream.
+// Because msgstream is bound to the rootcoord task, so we transfer each broadcast operation into a ddl task.
+// to make sure the timetick rule.
+// The Msgstream will be deprecated since 2.6.0, so we make a single module to hold it.
+type msgstreamAppendOperator struct {
+	core    *Core
+	walName string
+}
+
+// AppendMessages implements the AppendOperator interface for broadcaster service at streaming service.
+func (m *msgstreamAppendOperator) AppendMessages(ctx context.Context, msgs ...message.MutableMessage) types.AppendResponses {
+	t := &broadcastTask{
+		baseTask:     newBaseTask(ctx, m.core),
+		msgs:         msgs,
+		walName:      m.walName,
+		resultFuture: syncutil.NewFuture[types.AppendResponses](),
+	}
+
+	if err := m.core.scheduler.AddTask(t); err != nil {
+		resp := types.NewAppendResponseN(len(msgs))
+		resp.FillAllError(err)
+		return resp
+	}
+
+	result, err := t.resultFuture.GetWithContext(ctx)
+	if err != nil {
+		resp := types.NewAppendResponseN(len(msgs))
+		resp.FillAllError(err)
+		return resp
+	}
+	return result
+}

internal/rootcoord/dml_channels.go

@@ -327,6 +327,9 @@ func (d *dmlChannels) broadcastMark(chanNames []string, pack *msgstream.MsgPack)
 					result[cn] = id.Serialize()
 				}
 			}
+		} else {
+			dms.mutex.RUnlock()
+			return nil, errors.Newf("channel not in use: %s", chanName)
 		}
 		dms.mutex.RUnlock()
 	}

internal/rootcoord/root_coord.go

@@ -46,6 +46,7 @@ import (
 	kvmetestore "github.com/milvus-io/milvus/internal/metastore/kv/rootcoord"
 	"github.com/milvus-io/milvus/internal/metastore/model"
 	streamingcoord "github.com/milvus-io/milvus/internal/streamingcoord/server"
+	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster/registry"
 	tso2 "github.com/milvus-io/milvus/internal/tso"
 	"github.com/milvus-io/milvus/internal/types"
 	"github.com/milvus-io/milvus/internal/util/dependency"
@@ -766,6 +767,10 @@ func (c *Core) startInternal() error {
 	sessionutil.SaveServerInfo(typeutil.RootCoordRole, c.session.ServerID)
 	log.Info("rootcoord startup successfully")
 
+	// regster the core as a appendoperator for broadcast service.
+	// TODO: should be removed at 2.6.0.
+	// Add the wal accesser to the broadcaster registry for making broadcast operation.
+	registry.Register(registry.AppendOperatorTypeMsgstream, newMsgStreamAppendOperator(c))
 	return nil
 }
 

internal/rootcoord/root_coord_test.go

@@ -34,6 +34,7 @@ import (
 	"github.com/milvus-io/milvus/internal/metastore/model"
 	"github.com/milvus-io/milvus/internal/mocks"
 	mockrootcoord "github.com/milvus-io/milvus/internal/rootcoord/mocks"
+	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster/registry"
 	"github.com/milvus-io/milvus/internal/util/dependency"
 	kvfactory "github.com/milvus-io/milvus/internal/util/dependency/kv"
 	"github.com/milvus-io/milvus/internal/util/proxyutil"
@@ -1356,6 +1357,7 @@ func TestCore_startTimeTickLoop(t *testing.T) {
 func TestRootcoord_EnableActiveStandby(t *testing.T) {
 	randVal := rand.Int()
 	paramtable.Init()
+	registry.ResetRegistration()
 	Params.Save("etcd.rootPath", fmt.Sprintf("/%d", randVal))
 	// Need to reset global etcd to follow new path
 	kvfactory.CloseEtcdClient()
@@ -1416,6 +1418,7 @@ func TestRootcoord_EnableActiveStandby(t *testing.T) {
 func TestRootcoord_DisableActiveStandby(t *testing.T) {
 	randVal := rand.Int()
 	paramtable.Init()
+	registry.ResetRegistration()
 	Params.Save("etcd.rootPath", fmt.Sprintf("/%d", randVal))
 	// Need to reset global etcd to follow new path
 	kvfactory.CloseEtcdClient()

internal/streamingcoord/client/client.go

@@ -13,6 +13,7 @@ import (
 	"github.com/milvus-io/milvus/internal/streamingcoord/client/assignment"
 	"github.com/milvus-io/milvus/internal/streamingcoord/client/broadcast"
 	"github.com/milvus-io/milvus/internal/util/sessionutil"
+	"github.com/milvus-io/milvus/internal/util/streamingutil"
 	"github.com/milvus-io/milvus/internal/util/streamingutil/service/balancer/picker"
 	streamingserviceinterceptor "github.com/milvus-io/milvus/internal/util/streamingutil/service/interceptor"
 	"github.com/milvus-io/milvus/internal/util/streamingutil/service/lazygrpc"
@@ -43,9 +44,14 @@ type BroadcastService interface {
 
 // Client is the interface of log service client.
 type Client interface {
+	// Broadcast access broadcast service.
+	// Broadcast service will always be available.
+	// When streaming service is enabled, the broadcast will use the streaming service.
+	// When streaming service is disabled, the broadcast will use legacy msgstream.
 	Broadcast() BroadcastService
 
 	// Assignment access assignment service.
+	// Assignment service will only be available when streaming service is enabled.
 	Assignment() AssignmentService
 
 	// Close close the client.
@@ -68,12 +74,16 @@ func NewClient(etcdCli *clientv3.Client) Client {
 			dialOptions...,
 		)
 	})
-	assignmentService := lazygrpc.WithServiceCreator(conn, streamingpb.NewStreamingCoordAssignmentServiceClient)
+	var assignmentServiceImpl *assignment.AssignmentServiceImpl
+	if streamingutil.IsStreamingServiceEnabled() {
+		assignmentService := lazygrpc.WithServiceCreator(conn, streamingpb.NewStreamingCoordAssignmentServiceClient)
+		assignmentServiceImpl = assignment.NewAssignmentService(assignmentService)
+	}
 	broadcastService := lazygrpc.WithServiceCreator(conn, streamingpb.NewStreamingCoordBroadcastServiceClient)
 	return &clientImpl{
 		conn:              conn,
 		rb:                rb,
-		assignmentService: assignment.NewAssignmentService(assignmentService),
+		assignmentService: assignmentServiceImpl,
 		broadcastService:  broadcast.NewBroadcastService(util.MustSelectWALName(), broadcastService),
 	}
 }

internal/streamingcoord/client/client_impl.go

@@ -26,7 +26,9 @@ func (c *clientImpl) Assignment() AssignmentService {
 
 // Close close the client.
 func (c *clientImpl) Close() {
-	c.assignmentService.Close()
+	if c.assignmentService != nil {
+		c.assignmentService.Close()
+	}
 	c.conn.Close()
 	c.rb.Close()
 }

internal/streamingcoord/server/broadcaster/broadcaster.go

@@ -3,7 +3,7 @@ package broadcaster
 import (
 	"context"
 
-	"github.com/milvus-io/milvus/internal/distributed/streaming"
+	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster/registry"
 	"github.com/milvus-io/milvus/pkg/streaming/util/message"
 	"github.com/milvus-io/milvus/pkg/streaming/util/types"
 )
@@ -16,9 +16,4 @@ type Broadcaster interface {
 	Close()
 }
 
-// AppendOperator is used to append messages, there's only two implement of this interface:
-// 1. streaming.WAL()
-// 2. old msgstream interface
-type AppendOperator interface {
-	AppendMessages(ctx context.Context, msgs ...message.MutableMessage) streaming.AppendResponses
-}
+type AppendOperator = registry.AppendOperator

internal/streamingcoord/server/broadcaster/broadcaster_impl.go

@@ -15,13 +15,15 @@ import (
 	"github.com/milvus-io/milvus/pkg/streaming/util/message"
 	"github.com/milvus-io/milvus/pkg/streaming/util/types"
 	"github.com/milvus-io/milvus/pkg/util/contextutil"
+	"github.com/milvus-io/milvus/pkg/util/hardware"
+	"github.com/milvus-io/milvus/pkg/util/paramtable"
 	"github.com/milvus-io/milvus/pkg/util/syncutil"
 	"github.com/milvus-io/milvus/pkg/util/typeutil"
 )
 
 func RecoverBroadcaster(
 	ctx context.Context,
-	appendOperator AppendOperator,
+	appendOperator *syncutil.Future[AppendOperator],
 ) (Broadcaster, error) {
 	logger := resource.Resource().Logger().With(log.FieldComponent("broadcaster"))
 	tasks, err := resource.Resource().StreamingCatalog().ListBroadcastTask(ctx)
@@ -61,7 +63,7 @@ type broadcasterImpl struct {
 	pendingChan            chan *broadcastTask
 	backoffChan            chan *broadcastTask
 	workerChan             chan *broadcastTask
-	appendOperator         AppendOperator
+	appendOperator         *syncutil.Future[AppendOperator] // TODO: we can remove those lazy future in 2.6.0, by remove the msgstream broadcaster.
 }
 
 // Broadcast broadcasts the message to all channels.
@@ -126,21 +128,34 @@ func (b *broadcasterImpl) Close() {
 
 // execute the broadcaster
 func (b *broadcasterImpl) execute() {
-	b.logger.Info("broadcaster start to execute")
+	workers := int(float64(hardware.GetCPUNum()) * paramtable.Get().StreamingCfg.WALBroadcasterConcurrencyRatio.GetAsFloat())
+	if workers < 1 {
+		workers = 1
+	}
+	b.logger.Info("broadcaster start to execute", zap.Int("workerNum", workers))
+
 	defer func() {
 		b.backgroundTaskNotifier.Finish(struct{}{})
 		b.logger.Info("broadcaster execute exit")
 	}()
 
+	// Wait for appendOperator ready
+	appendOperator, err := b.appendOperator.GetWithContext(b.backgroundTaskNotifier.Context())
+	if err != nil {
+		b.logger.Info("broadcaster is closed before appendOperator ready")
+		return
+	}
+	b.logger.Info("broadcaster appendOperator ready, begin to start workers and dispatch")
+
 	// Start n workers to handle the broadcast task.
 	wg := sync.WaitGroup{}
-	for i := 0; i < 4; i++ {
+	for i := 0; i < workers; i++ {
 		i := i
 		// Start n workers to handle the broadcast task.
 		wg.Add(1)
 		go func() {
 			defer wg.Done()
-			b.worker(i)
+			b.worker(i, appendOperator)
 		}()
 	}
 	defer wg.Wait()
@@ -174,8 +189,13 @@ func (b *broadcasterImpl) dispatch() {
 			b.backoffs.Push(task)
 		case <-nextBackOff:
 			// backoff is done, move all the backoff done task into pending to retry.
+			newPops := make([]*broadcastTask, 0)
 			for b.backoffs.Len() > 0 && b.backoffs.Peek().NextInterval() < time.Millisecond {
-				b.pendings = append(b.pendings, b.backoffs.Pop())
+				newPops = append(newPops, b.backoffs.Pop())
+			}
+			if len(newPops) > 0 {
+				// Push the backoff task into pendings front.
+				b.pendings = append(newPops, b.pendings...)
 			}
 		case workerChan <- nextTask:
 			// The task is sent to worker, remove it from pending list.
@@ -184,9 +204,10 @@ func (b *broadcasterImpl) dispatch() {
 	}
 }
 
-func (b *broadcasterImpl) worker(no int) {
+func (b *broadcasterImpl) worker(no int, appendOperator AppendOperator) {
+	logger := b.logger.With(zap.Int("workerNo", no))
 	defer func() {
-		b.logger.Info("broadcaster worker exit", zap.Int("no", no))
+		logger.Info("broadcaster worker exit")
 	}()
 
 	for {
@@ -194,7 +215,7 @@ func (b *broadcasterImpl) worker(no int) {
 		case <-b.backgroundTaskNotifier.Context().Done():
 			return
 		case task := <-b.workerChan:
-			if err := task.Poll(b.backgroundTaskNotifier.Context(), b.appendOperator); err != nil {
+			if err := task.Execute(b.backgroundTaskNotifier.Context(), appendOperator); err != nil {
 				// If the task is not done, repush it into pendings and retry infinitely.
 				select {
 				case <-b.backgroundTaskNotifier.Context().Done():

internal/streamingcoord/server/broadcaster/broadcaster_test.go

@@ -12,7 +12,6 @@ import (
 	"go.uber.org/atomic"
 
 	"github.com/milvus-io/milvus-proto/go-api/v2/msgpb"
-	"github.com/milvus-io/milvus/internal/distributed/streaming"
 	"github.com/milvus-io/milvus/internal/mocks/mock_metastore"
 	"github.com/milvus-io/milvus/internal/mocks/streamingcoord/server/mock_broadcaster"
 	"github.com/milvus-io/milvus/internal/streamingcoord/server/resource"
@@ -23,10 +22,13 @@ import (
 	"github.com/milvus-io/milvus/pkg/streaming/util/message"
 	"github.com/milvus-io/milvus/pkg/streaming/util/types"
 	"github.com/milvus-io/milvus/pkg/streaming/walimpls/impls/walimplstest"
+	"github.com/milvus-io/milvus/pkg/util/paramtable"
 	"github.com/milvus-io/milvus/pkg/util/syncutil"
 )
 
 func TestBroadcaster(t *testing.T) {
+	paramtable.Init()
+
 	meta := mock_metastore.NewMockStreamingCoordCataLog(t)
 	meta.EXPECT().ListBroadcastTask(mock.Anything).
 		RunAndReturn(func(ctx context.Context) ([]*streamingpb.BroadcastTask, error) {
@@ -39,7 +41,7 @@ func TestBroadcaster(t *testing.T) {
 	done := atomic.NewInt64(0)
 	meta.EXPECT().SaveBroadcastTask(mock.Anything, mock.Anything).RunAndReturn(func(ctx context.Context, bt *streamingpb.BroadcastTask) error {
 		// may failure
-		if rand.Int31n(10) < 5 {
+		if rand.Int31n(10) < 3 {
 			return errors.New("save task failed")
 		}
 		if bt.State == streamingpb.BroadcastTaskState_BROADCAST_TASK_STATE_DONE {
@@ -58,7 +60,7 @@ func TestBroadcaster(t *testing.T) {
 	assert.NotNil(t, bc)
 	assert.Eventually(t, func() bool {
 		return appended.Load() == 6 && done.Load() == 3
-	}, 10*time.Second, 10*time.Millisecond)
+	}, 30*time.Second, 10*time.Millisecond)
 
 	var result *types.BroadcastAppendResult
 	for {
@@ -73,7 +75,7 @@ func TestBroadcaster(t *testing.T) {
 
 	assert.Eventually(t, func() bool {
 		return done.Load() == 4
-	}, 10*time.Second, 10*time.Millisecond)
+	}, 30*time.Second, 10*time.Millisecond)
 
 	// TODO: error path.
 	bc.Close()
@@ -83,23 +85,23 @@ func TestBroadcaster(t *testing.T) {
 	assert.Nil(t, result)
 }
 
-func createOpeartor(t *testing.T) (AppendOperator, *atomic.Int64) {
+func createOpeartor(t *testing.T) (*syncutil.Future[AppendOperator], *atomic.Int64) {
 	id := atomic.NewInt64(1)
 	appended := atomic.NewInt64(0)
 	operator := mock_broadcaster.NewMockAppendOperator(t)
-	f := func(ctx context.Context, msgs ...message.MutableMessage) streaming.AppendResponses {
-		resps := streaming.AppendResponses{
-			Responses: make([]streaming.AppendResponse, len(msgs)),
+	f := func(ctx context.Context, msgs ...message.MutableMessage) types.AppendResponses {
+		resps := types.AppendResponses{
+			Responses: make([]types.AppendResponse, len(msgs)),
 		}
 		for idx := range msgs {
 			newID := walimplstest.NewTestMessageID(id.Inc())
-			if rand.Int31n(10) < 5 {
-				resps.Responses[idx] = streaming.AppendResponse{
+			if rand.Int31n(10) < 3 {
+				resps.Responses[idx] = types.AppendResponse{
 					Error: errors.New("append failed"),
 				}
 				continue
 			}
-			resps.Responses[idx] = streaming.AppendResponse{
+			resps.Responses[idx] = types.AppendResponse{
 				AppendResult: &types.AppendResult{
 					MessageID: newID,
 					TimeTick:  uint64(time.Now().UnixMilli()),
@@ -114,7 +116,10 @@ func createOpeartor(t *testing.T) (AppendOperator, *atomic.Int64) {
 	operator.EXPECT().AppendMessages(mock.Anything, mock.Anything, mock.Anything).RunAndReturn(f)
 	operator.EXPECT().AppendMessages(mock.Anything, mock.Anything, mock.Anything, mock.Anything).RunAndReturn(f)
 	operator.EXPECT().AppendMessages(mock.Anything, mock.Anything, mock.Anything, mock.Anything, mock.Anything).RunAndReturn(f)
-	return operator, appended
+
+	fOperator := syncutil.NewFuture[AppendOperator]()
+	fOperator.Set(operator)
+	return fOperator, appended
 }
 
 func createNewBroadcastMsg(vchannels []string) message.BroadcastMutableMessage {

internal/streamingcoord/server/broadcaster/registry/append_operator.go

@@ -0,0 +1,42 @@
+package registry
+
+import (
+	"context"
+
+	"github.com/milvus-io/milvus/internal/util/streamingutil"
+	"github.com/milvus-io/milvus/pkg/streaming/util/message"
+	"github.com/milvus-io/milvus/pkg/streaming/util/types"
+	"github.com/milvus-io/milvus/pkg/util/syncutil"
+)
+
+type AppendOperatorType int
+
+const (
+	AppendOperatorTypeMsgstream AppendOperatorType = iota + 1
+	AppendOperatorTypeStreaming
+)
+
+var localRegistry = make(map[AppendOperatorType]*syncutil.Future[AppendOperator])
+
+// AppendOperator is used to append messages, there's only two implement of this interface:
+// 1. streaming.WAL()
+// 2. old msgstream interface
+type AppendOperator interface {
+	AppendMessages(ctx context.Context, msgs ...message.MutableMessage) types.AppendResponses
+}
+
+func init() {
+	localRegistry[AppendOperatorTypeMsgstream] = syncutil.NewFuture[AppendOperator]()
+	localRegistry[AppendOperatorTypeStreaming] = syncutil.NewFuture[AppendOperator]()
+}
+
+func Register(typ AppendOperatorType, op AppendOperator) {
+	localRegistry[typ].Set(op)
+}
+
+func GetAppendOperator() *syncutil.Future[AppendOperator] {
+	if streamingutil.IsStreamingServiceEnabled() {
+		return localRegistry[AppendOperatorTypeStreaming]
+	}
+	return localRegistry[AppendOperatorTypeMsgstream]
+}

internal/streamingcoord/server/broadcaster/registry/test_utility.go

@@ -0,0 +1,12 @@
+//go:build test
+// +build test
+
+package registry
+
+import "github.com/milvus-io/milvus/pkg/util/syncutil"
+
+func ResetRegistration() {
+	localRegistry = make(map[AppendOperatorType]*syncutil.Future[AppendOperator])
+	localRegistry[AppendOperatorTypeMsgstream] = syncutil.NewFuture[AppendOperator]()
+	localRegistry[AppendOperatorTypeStreaming] = syncutil.NewFuture[AppendOperator]()
+}

internal/streamingcoord/server/broadcaster/task.go

@@ -49,15 +49,17 @@ type broadcastTask struct {
 	*typeutil.BackoffWithInstant
 }
 
-// Poll polls the task, return nil if the task is done, otherwise not done.
-// Poll can be repeated called until the task is done.
-func (b *broadcastTask) Poll(ctx context.Context, operator AppendOperator) error {
+// Execute reexecute the task, return nil if the task is done, otherwise not done.
+// Execute can be repeated called until the task is done.
+// Same semantics as the `Poll` operation in eventloop.
+func (b *broadcastTask) Execute(ctx context.Context, operator AppendOperator) error {
 	if len(b.pendingMessages) > 0 {
 		b.logger.Debug("broadcast task is polling to make sent...", zap.Int("pendingMessages", len(b.pendingMessages)))
 		resps := operator.AppendMessages(ctx, b.pendingMessages...)
 		newPendings := make([]message.MutableMessage, 0)
 		for idx, resp := range resps.Responses {
 			if resp.Error != nil {
+				b.logger.Warn("broadcast task append message failed", zap.Int("idx", idx), zap.Error(resp.Error))
 				newPendings = append(newPendings, b.pendingMessages[idx])
 				continue
 			}
@@ -67,7 +69,7 @@ func (b *broadcastTask) Poll(ctx context.Context, operator AppendOperator) error
 		if len(newPendings) == 0 {
 			b.future.Set(&types.BroadcastAppendResult{AppendResults: b.appendResult})
 		}
-		b.logger.Info("broadcast task make a new broadcast done", zap.Int("pendingMessages", len(b.pendingMessages)))
+		b.logger.Info("broadcast task make a new broadcast done", zap.Int("backoffRetryMessages", len(b.pendingMessages)))
 	}
 	if len(b.pendingMessages) == 0 {
 		// There's no more pending message, mark the task as done.

internal/streamingcoord/server/server.go

@@ -9,6 +9,7 @@ import (
 	"github.com/milvus-io/milvus/internal/streamingcoord/server/balancer"
 	_ "github.com/milvus-io/milvus/internal/streamingcoord/server/balancer/policy" // register the balancer policy
 	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster"
+	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster/registry"
 	"github.com/milvus-io/milvus/internal/streamingcoord/server/service"
 	"github.com/milvus-io/milvus/internal/util/sessionutil"
 	"github.com/milvus-io/milvus/internal/util/streamingutil"
@@ -69,7 +70,7 @@ func (s *Server) initBasicComponent(ctx context.Context) (err error) {
 	// So we need to recover it.
 	futures = append(futures, conc.Go(func() (struct{}, error) {
 		s.logger.Info("start recovery broadcaster...")
-		broadcaster, err := broadcaster.RecoverBroadcaster(ctx, broadcaster.NewAppendOperator())
+		broadcaster, err := broadcaster.RecoverBroadcaster(ctx, registry.GetAppendOperator())
 		if err != nil {
 			s.logger.Warn("recover broadcaster failed", zap.Error(err))
 			return struct{}{}, err

pkg/streaming/util/message/adaptor/broadcast_message.go

@@ -0,0 +1,25 @@
+package adaptor
+
+import (
+	"github.com/cockroachdb/errors"
+
+	"github.com/milvus-io/milvus/pkg/mq/msgstream"
+	"github.com/milvus-io/milvus/pkg/streaming/util/message"
+)
+
+func NewMsgPackFromMutableMessageV1(msg message.MutableMessage) (msgstream.TsMsg, error) {
+	if msg.Version() != message.VersionV1 {
+		return nil, errors.New("Invalid message version")
+	}
+
+	tsMsg, err := unmashalerDispatcher.Unmarshal(msg.Payload(), MustGetCommonpbMsgTypeFromMessageType(msg.MessageType()))
+	if err != nil {
+		return nil, errors.Wrap(err, "Failed to unmarshal message")
+	}
+	return recoverMutableMessageFromHeader(tsMsg, msg)
+}
+
+func recoverMutableMessageFromHeader(tsMsg msgstream.TsMsg, _ message.MutableMessage) (msgstream.TsMsg, error) {
+	// TODO: fillback the header information to tsMsg
+	return tsMsg, nil
+}

pkg/streaming/util/types/responses.go

@@ -0,0 +1,113 @@
+package types
+
+import (
+	"google.golang.org/protobuf/proto"
+	"google.golang.org/protobuf/types/known/anypb"
+
+	"github.com/milvus-io/milvus/pkg/proto/messagespb"
+	"github.com/milvus-io/milvus/pkg/proto/streamingpb"
+	"github.com/milvus-io/milvus/pkg/streaming/util/message"
+)
+
+// BroadcastAppendResult is the result of broadcast append operation.
+type BroadcastAppendResult struct {
+	AppendResults map[string]*AppendResult // make the channel name to the append result.
+}
+
+// GetAppendResult returns the append result of the given channel.
+func (r *BroadcastAppendResult) GetAppendResult(channelName string) *AppendResult {
+	return r.AppendResults[channelName]
+}
+
+// AppendResult is the result of append operation.
+type AppendResult struct {
+	// MessageID is generated by underlying walimpls.
+	MessageID message.MessageID
+
+	// TimeTick is the time tick of the message.
+	// Set by timetick interceptor.
+	TimeTick uint64
+
+	// TxnCtx is the transaction context of the message.
+	// If the message is not belong to a transaction, the TxnCtx will be nil.
+	TxnCtx *message.TxnContext
+
+	// Extra is the extra information of the append result.
+	Extra *anypb.Any
+}
+
+// GetExtra unmarshal the extra information to the given message.
+func (r *AppendResult) GetExtra(m proto.Message) error {
+	return anypb.UnmarshalTo(r.Extra, m, proto.UnmarshalOptions{
+		DiscardUnknown: true,
+		AllowPartial:   true,
+	})
+}
+
+// IntoProto converts the append result to proto.
+func (r *AppendResult) IntoProto() *streamingpb.ProduceMessageResponseResult {
+	return &streamingpb.ProduceMessageResponseResult{
+		Id: &messagespb.MessageID{
+			Id: r.MessageID.Marshal(),
+		},
+		Timetick:   r.TimeTick,
+		TxnContext: r.TxnCtx.IntoProto(),
+		Extra:      r.Extra,
+	}
+}
+
+// NewAppendResponseN creates a new append response.
+func NewAppendResponseN(n int) AppendResponses {
+	return AppendResponses{
+		Responses: make([]AppendResponse, n),
+	}
+}
+
+// AppendResponse is the response of one append operation.
+type AppendResponse struct {
+	AppendResult *AppendResult
+	Error        error
+}
+
+// AppendResponses is the response of append operation.
+type AppendResponses struct {
+	Responses []AppendResponse
+}
+
+func (a AppendResponses) MaxTimeTick() uint64 {
+	var maxTimeTick uint64
+	for _, r := range a.Responses {
+		if r.AppendResult != nil && r.AppendResult.TimeTick > maxTimeTick {
+			maxTimeTick = r.AppendResult.TimeTick
+		}
+	}
+	return maxTimeTick
+}
+
+// UnwrapFirstError returns the first error in the responses.
+func (a AppendResponses) UnwrapFirstError() error {
+	for _, r := range a.Responses {
+		if r.Error != nil {
+			return r.Error
+		}
+	}
+	return nil
+}
+
+// FillAllError fills all the responses with the same error.
+func (a *AppendResponses) FillAllError(err error) {
+	for i := range a.Responses {
+		a.Responses[i].Error = err
+	}
+}
+
+// FillResponseAtIdx fill the response at idx
+func (a *AppendResponses) FillResponseAtIdx(resp AppendResponse, idx int) {
+	a.Responses[idx] = resp
+}
+
+func (a *AppendResponses) FillAllResponse(resp AppendResponse) {
+	for i := range a.Responses {
+		a.Responses[i] = resp
+	}
+}

pkg/streaming/util/types/streaming_node.go

@@ -4,12 +4,8 @@ import (
 	"context"
 
 	"github.com/cockroachdb/errors"
-	"google.golang.org/protobuf/proto"
-	"google.golang.org/protobuf/types/known/anypb"
 
-	"github.com/milvus-io/milvus/pkg/proto/messagespb"
 	"github.com/milvus-io/milvus/pkg/proto/streamingpb"
-	"github.com/milvus-io/milvus/pkg/streaming/util/message"
 	"github.com/milvus-io/milvus/pkg/util/typeutil"
 )
 
@@ -88,50 +84,3 @@ func (n *StreamingNodeStatus) ErrorOfNode() error {
 	}
 	return n.Err
 }
-
-// BroadcastAppendResult is the result of broadcast append operation.
-type BroadcastAppendResult struct {
-	AppendResults map[string]*AppendResult // make the channel name to the append result.
-}
-
-// GetAppendResult returns the append result of the given channel.
-func (r *BroadcastAppendResult) GetAppendResult(channelName string) *AppendResult {
-	return r.AppendResults[channelName]
-}
-
-// AppendResult is the result of append operation.
-type AppendResult struct {
-	// MessageID is generated by underlying walimpls.
-	MessageID message.MessageID
-
-	// TimeTick is the time tick of the message.
-	// Set by timetick interceptor.
-	TimeTick uint64
-
-	// TxnCtx is the transaction context of the message.
-	// If the message is not belong to a transaction, the TxnCtx will be nil.
-	TxnCtx *message.TxnContext
-
-	// Extra is the extra information of the append result.
-	Extra *anypb.Any
-}
-
-// GetExtra unmarshal the extra information to the given message.
-func (r *AppendResult) GetExtra(m proto.Message) error {
-	return anypb.UnmarshalTo(r.Extra, m, proto.UnmarshalOptions{
-		DiscardUnknown: true,
-		AllowPartial:   true,
-	})
-}
-
-// IntoProto converts the append result to proto.
-func (r *AppendResult) IntoProto() *streamingpb.ProduceMessageResponseResult {
-	return &streamingpb.ProduceMessageResponseResult{
-		Id: &messagespb.MessageID{
-			Id: r.MessageID.Marshal(),
-		},
-		Timetick:   r.TimeTick,
-		TxnContext: r.TxnCtx.IntoProto(),
-		Extra:      r.Extra,
-	}
-}

pkg/util/paramtable/component_param.go

@@ -4828,6 +4828,9 @@ type streamingConfig struct {
 	WALBalancerBackoffInitialInterval ParamItem `refreshable:"true"`
 	WALBalancerBackoffMultiplier      ParamItem `refreshable:"true"`
 
+	// broadcaster
+	WALBroadcasterConcurrencyRatio ParamItem `refreshable:"false"`
+
 	// txn
 	TxnDefaultKeepaliveTimeout ParamItem `refreshable:"true"`
 }
@@ -4861,6 +4864,15 @@ It's ok to set it into duration string, such as 30s or 1m30s, see time.ParseDura
 	}
 	p.WALBalancerBackoffMultiplier.Init(base.mgr)
 
+	p.WALBroadcasterConcurrencyRatio = ParamItem{
+		Key:          "streaming.walBroadcaster.concurrencyRatio",
+		Version:      "2.5.4",
+		Doc:          `The concurrency ratio based on number of CPU for wal broadcaster, 1 by default.`,
+		DefaultValue: "1",
+		Export:       true,
+	}
+	p.WALBroadcasterConcurrencyRatio.Init(base.mgr)
+
 	// txn
 	p.TxnDefaultKeepaliveTimeout = ParamItem{
 		Key:          "streaming.txn.defaultKeepaliveTimeout",

pkg/util/paramtable/component_param_test.go

@@ -614,14 +614,17 @@ func TestComponentParam(t *testing.T) {
 		assert.Equal(t, 1*time.Minute, params.StreamingCfg.WALBalancerTriggerInterval.GetAsDurationByParse())
 		assert.Equal(t, 50*time.Millisecond, params.StreamingCfg.WALBalancerBackoffInitialInterval.GetAsDurationByParse())
 		assert.Equal(t, 2.0, params.StreamingCfg.WALBalancerBackoffMultiplier.GetAsFloat())
+		assert.Equal(t, 1.0, params.StreamingCfg.WALBroadcasterConcurrencyRatio.GetAsFloat())
 		assert.Equal(t, 10*time.Second, params.StreamingCfg.TxnDefaultKeepaliveTimeout.GetAsDurationByParse())
 		params.Save(params.StreamingCfg.WALBalancerTriggerInterval.Key, "50s")
 		params.Save(params.StreamingCfg.WALBalancerBackoffInitialInterval.Key, "50s")
 		params.Save(params.StreamingCfg.WALBalancerBackoffMultiplier.Key, "3.5")
+		params.Save(params.StreamingCfg.WALBroadcasterConcurrencyRatio.Key, "1.5")
 		params.Save(params.StreamingCfg.TxnDefaultKeepaliveTimeout.Key, "3500ms")
 		assert.Equal(t, 50*time.Second, params.StreamingCfg.WALBalancerTriggerInterval.GetAsDurationByParse())
 		assert.Equal(t, 50*time.Second, params.StreamingCfg.WALBalancerBackoffInitialInterval.GetAsDurationByParse())
 		assert.Equal(t, 3.5, params.StreamingCfg.WALBalancerBackoffMultiplier.GetAsFloat())
+		assert.Equal(t, 1.5, params.StreamingCfg.WALBroadcasterConcurrencyRatio.GetAsFloat())
 		assert.Equal(t, 3500*time.Millisecond, params.StreamingCfg.TxnDefaultKeepaliveTimeout.GetAsDurationByParse())
 	})
 

tests/integration/coorddownsearch/search_after_coord_down_test.go

@@ -30,6 +30,7 @@ import (
 	"github.com/milvus-io/milvus-proto/go-api/v2/commonpb"
 	"github.com/milvus-io/milvus-proto/go-api/v2/milvuspb"
 	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
+	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster/registry"
 	"github.com/milvus-io/milvus/pkg/common"
 	"github.com/milvus-io/milvus/pkg/log"
 	"github.com/milvus-io/milvus/pkg/util/funcutil"
@@ -302,6 +303,8 @@ func (s *CoordDownSearch) searchAfterCoordDown() float64 {
 	s.searchFailed(searchCollectionName, Dim, commonpb.ConsistencyLevel_Strong)
 	log.Info(fmt.Sprintf("=========================Failed search cost: %fs=========================", time.Since(failedStart).Seconds()))
 
+	registry.ResetRegistration()
+
 	log.Info("=========================restart Root Coordinators=========================")
 	c.StartRootCoord()
 	s.search(searchCollectionName, Dim, commonpb.ConsistencyLevel_Eventually)

tests/integration/coordrecovery/coord_recovery_test.go

@@ -30,6 +30,7 @@ import (
 
 	"github.com/milvus-io/milvus-proto/go-api/v2/milvuspb"
 	"github.com/milvus-io/milvus-proto/go-api/v2/schemapb"
+	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster/registry"
 	"github.com/milvus-io/milvus/pkg/common"
 	"github.com/milvus-io/milvus/pkg/log"
 	"github.com/milvus-io/milvus/pkg/util/funcutil"
@@ -242,6 +243,8 @@ func (s *CoordSwitchSuite) switchCoord() float64 {
 	log.Info("=========================Coordinators stopped=========================", zap.Duration("elapsed", time.Since(start)))
 	start = time.Now()
 
+	registry.ResetRegistration()
+
 	c.StartRootCoord()
 	log.Info("=========================RootCoord restarted=========================")
 	c.StartDataCoord()

tests/integration/suite.go

@@ -30,6 +30,7 @@ import (
 	"go.uber.org/zap/zapcore"
 
 	"github.com/milvus-io/milvus-proto/go-api/v2/milvuspb"
+	"github.com/milvus-io/milvus/internal/streamingcoord/server/broadcaster/registry"
 	"github.com/milvus-io/milvus/internal/util/hookutil"
 	"github.com/milvus-io/milvus/pkg/log"
 	"github.com/milvus-io/milvus/pkg/util/etcd"
@@ -169,4 +170,5 @@ func (s *MiniClusterSuite) TearDownTest() {
 	if s.Cluster != nil {
 		s.Cluster.Stop()
 	}
+	registry.ResetRegistration()
 }