fix: Datanode stop progress stuck at writer buffer memory check (#38274)

issue: #38273

Signed-off-by: Wei Liu <wei.liu@zilliz.com>

internal/flushcommon/writebuffer/manager.go

@@ -77,13 +77,19 @@ func (m *bufferManager) Start() {
 }
 
 func (m *bufferManager) check() {
-	ticker := time.NewTimer(paramtable.Get().DataNodeCfg.MemoryCheckInterval.GetAsDuration(time.Millisecond))
-	defer ticker.Stop()
+	timer := time.NewTimer(paramtable.Get().DataNodeCfg.MemoryCheckInterval.GetAsDuration(time.Millisecond))
+	defer timer.Stop()
 	for {
 		select {
-		case <-ticker.C:
+		case <-timer.C:
 			m.memoryCheck()
-			ticker.Reset(paramtable.Get().DataNodeCfg.MemoryCheckInterval.GetAsDuration(time.Millisecond))
+			if !timer.Stop() {
+				select {
+				case <-timer.C:
+				default:
+				}
+			}
+			timer.Reset(paramtable.Get().DataNodeCfg.MemoryCheckInterval.GetAsDuration(time.Millisecond))
 		case <-m.ch.CloseCh():
 			log.Info("buffer manager memory check stopped")
 			return
@@ -114,6 +120,13 @@ func (m *bufferManager) memoryCheck() {
 			return mem / 1024 / 1024
 		}
 
+		select {
+		case <-m.ch.CloseCh():
+			log.Info("stop memory check due to manager stop")
+			return
+		default:
+		}
+
 		m.buffers.Range(func(chanName string, buf WriteBuffer) bool {
 			size := buf.MemorySize()
 			total += size

internal/flushcommon/writebuffer/manager_test.go

@@ -262,6 +262,39 @@ func (s *ManagerSuite) TestMemoryCheck() {
 	wb.AssertExpectations(s.T())
 }
 
+func (s *ManagerSuite) TestStopDuringMemoryCheck() {
+	manager := s.manager
+	param := paramtable.Get()
+
+	param.Save(param.DataNodeCfg.MemoryCheckInterval.Key, "50")
+	param.Save(param.DataNodeCfg.MemoryForceSyncEnable.Key, "true")
+	param.Save(param.DataNodeCfg.MemoryForceSyncWatermark.Key, "0.7")
+
+	defer func() {
+		param.Reset(param.DataNodeCfg.MemoryCheckInterval.Key)
+		param.Reset(param.DataNodeCfg.MemoryForceSyncEnable.Key)
+		param.Reset(param.DataNodeCfg.MemoryForceSyncWatermark.Key)
+	}()
+
+	wb := NewMockWriteBuffer(s.T())
+
+	// mock the memory size reach water mark
+	memoryLimit := hardware.GetMemoryCount()
+	wb.EXPECT().MemorySize().RunAndReturn(func() int64 {
+		return int64(float64(memoryLimit) * 0.8)
+	}).Maybe()
+	//.Return(int64(float64(memoryLimit) * 0.6))
+	wb.EXPECT().EvictBuffer(mock.Anything).Maybe()
+	manager.buffers.Insert(s.channelName, wb)
+	manager.Start()
+
+	// wait memory check triggered
+	time.Sleep(200 * time.Millisecond)
+
+	// expect stop operation won't stuck
+	manager.Stop()
+}
+
 func TestManager(t *testing.T) {
 	suite.Run(t, new(ManagerSuite))
 }