Add Buffer for consumer channel (#9578)

Signed-off-by: Nxiaofan-luan <xiaofan.luan@zilliz.com>

internal/datanode/flow_graph_dmstream_input_node.go

@@ -19,6 +19,7 @@ package datanode
 import (
 	"context"
 	"fmt"
+	"time"
 
 	"github.com/milvus-io/milvus/internal/log"
 	"github.com/milvus-io/milvus/internal/proto/internalpb"
@@ -47,11 +48,13 @@ func newDmInputNode(ctx context.Context, seekPos *internalpb.MsgPosition, dmNode
 
 	if seekPos != nil {
 		seekPos.ChannelName = pchannelName
-		log.Debug("datanode Seek", zap.String("channelName", seekPos.GetChannelName()))
+		start := time.Now()
+		log.Debug("datanode begin to seek: " + seekPos.GetChannelName())
 		err = insertStream.Seek([]*internalpb.MsgPosition{seekPos})
 		if err != nil {
 			return nil, err
 		}
+		log.Debug("datanode Seek successfully: "+seekPos.GetChannelName(), zap.Int64("elapse ", time.Since(start).Milliseconds()))
 	}
 
 	node := flowgraph.NewInputNode(insertStream, "dmInputNode", dmNodeConfig.maxQueueLength, dmNodeConfig.maxParallelism)

internal/msgstream/mq_msgstream.go

@@ -874,11 +874,6 @@ func (ms *MqTtMsgStream) Seek(msgPositions []*internalpb.MsgPosition) error {
 		}
 		ms.addConsumer(consumer, mp.ChannelName)
 
-		//TODO: May cause problem
-		//if len(consumer.Chan()) == 0 {
-		//	return nil
-		//}
-
 		runLoop := true
 		for runLoop {
 			select {

internal/util/mqclient/pulsar_consumer.go

@@ -34,7 +34,7 @@ func (pc *pulsarConsumer) Subscription() string {
 func (pc *pulsarConsumer) Chan() <-chan ConsumerMessage {
 	if pc.msgChannel == nil {
 		pc.once.Do(func() {
-			pc.msgChannel = make(chan ConsumerMessage)
+			pc.msgChannel = make(chan ConsumerMessage, 256)
 			// this part handles msgstream expectation when the consumer is not seeked
 			// pulsar's default behavior is setting postition to the earliest pointer when client of the same subscription pointer is not acked
 			// yet, our message stream is to setting to the very start point of the topic

internal/util/mqclient/rmq_consumer.go

@@ -34,7 +34,7 @@ func (rc *RmqConsumer) Subscription() string {
 func (rc *RmqConsumer) Chan() <-chan ConsumerMessage {
 	if rc.msgChannel == nil {
 		rc.once.Do(func() {
-			rc.msgChannel = make(chan ConsumerMessage)
+			rc.msgChannel = make(chan ConsumerMessage, 256)
 			go func() {
 				for { //nolint:gosimple
 					select {