ipvs connection based graceful termination

pkg/proxy/ipvs/graceful_termination.go

@@ -17,13 +17,11 @@ limitations under the License.
 package ipvs
 
 import (
-	"container/list"
 	"sync"
 	"time"
 
 	"fmt"
 	"github.com/golang/glog"
-	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/apimachinery/pkg/util/wait"
 	utilipvs "k8s.io/kubernetes/pkg/util/ipvs"
 )
@@ -38,7 +36,6 @@ const (
 type listItem struct {
 	VirtualServer *utilipvs.VirtualServer
 	RealServer    *utilipvs.RealServer
-	ProcessAt     time.Time
 }
 
 // String return the unique real server name(with virtual server information)
@@ -53,8 +50,7 @@ func GetUniqueRSName(vs *utilipvs.VirtualServer, rs *utilipvs.RealServer) string
 
 type graceTerminateRSList struct {
 	lock sync.Mutex
-	list *list.List
-	set  sets.String
+	list map[string]*listItem
 }
 
 // add push an new element to the rsList
@@ -63,13 +59,12 @@ func (q *graceTerminateRSList) add(rs *listItem) bool {
 	defer q.lock.Unlock()
 
 	uniqueRS := rs.String()
-	if q.set.Has(uniqueRS) {
+	if _, ok := q.list[uniqueRS]; ok {
 		return false
 	}
-	glog.V(5).Infof("Pushing rs %v to graceful delete rsList: %+v", rs)
 
-	q.list.PushBack(rs)
-	q.set.Insert(uniqueRS)
+	glog.V(5).Infof("Adding rs %v to graceful delete rsList", rs)
+	q.list[uniqueRS] = rs
 	return true
 }
 
@@ -79,29 +74,30 @@ func (q *graceTerminateRSList) remove(rs *listItem) bool {
 	defer q.lock.Unlock()
 
 	uniqueRS := rs.String()
-	if !q.set.Has(uniqueRS) {
+	if _, ok := q.list[uniqueRS]; ok {
 		return false
 	}
-	q.set.Delete(uniqueRS)
-	for e := q.list.Front(); e.Next() == nil; e = e.Next() {
-		val := e.Value.(*listItem)
-		if val.String() == uniqueRS {
-			q.list.Remove(e)
-			return true
-		}
-	}
-	return false
+	delete(q.list, uniqueRS)
+	return true
 }
 
-// head return the first element from the rsList
-func (q *graceTerminateRSList) head() (*listItem, bool) {
+func (q *graceTerminateRSList) flushList(handler func(rsToDelete *listItem) (bool, error)) bool {
 	q.lock.Lock()
 	defer q.lock.Unlock()
-	if q.list.Len() == 0 {
-		return nil, false
+
+	success := true
+	for name, rs := range q.list {
+		deleted, err := handler(rs)
+		if err != nil {
+			glog.Errorf("Try delete rs %q err: %v", name, err)
+			success = false
+		}
+		if deleted {
+			glog.Infof("lw: remote out of the list: %s", name)
+			q.remove(rs)
+		}
 	}
-	result := q.list.Front().Value.(*listItem)
-	return result, true
+	return success
 }
 
 // exist check whether the specified unique RS is in the rsList
@@ -109,15 +105,9 @@ func (q *graceTerminateRSList) exist(uniqueRS string) (*listItem, bool) {
 	q.lock.Lock()
 	defer q.lock.Unlock()
 
-	if !q.set.Has(uniqueRS) {
+	if _, ok := q.list[uniqueRS]; ok {
 		return nil, false
 	}
-	for e := q.list.Front(); e.Next() == nil; e = e.Next() {
-		val := e.Value.(*listItem)
-		if val.String() == uniqueRS {
-			return val, true
-		}
-	}
 	return nil, false
 }
 
@@ -130,12 +120,10 @@ type GracefulTerminationManager struct {
 
 // NewGracefulTerminationManager create a gracefulTerminationManager to manage ipvs rs graceful termination work
 func NewGracefulTerminationManager(ipvs utilipvs.Interface) *GracefulTerminationManager {
-	l := list.New()
-	l.Init()
+	l := make(map[string]*listItem)
 	return &GracefulTerminationManager{
 		rsList: graceTerminateRSList{
 			list: l,
-			set:  sets.NewString(),
 		},
 		ipvs: ipvs,
 	}
@@ -149,38 +137,53 @@ func (m *GracefulTerminationManager) InTerminationList(uniqueRS string) bool {
 
 // GracefulDeleteRS to update rs weight to 0, and add rs to graceful terminate list
 func (m *GracefulTerminationManager) GracefulDeleteRS(vs *utilipvs.VirtualServer, rs *utilipvs.RealServer) error {
-	rs.Weight = 0
-	err := m.ipvs.UpdateRealServer(vs, rs)
-	if err != nil {
-		return err
-	}
-
+	// Try to delete rs before add it to graceful delete list
 	ele := &listItem{
 		VirtualServer: vs,
 		RealServer:    rs,
-		ProcessAt:     time.Now().Add(rsGracefulDeletePeriod),
+	}
+	deleted, err := m.deleteRsFunc(ele)
+	if err != nil {
+		glog.Errorf("Delete rs %q err: %v", err)
+	}
+	if deleted {
+		return nil
+	}
+	rs.Weight = 0
+	err = m.ipvs.UpdateRealServer(vs, rs)
+	if err != nil {
+		return err
 	}
 	glog.V(5).Infof("Adding an element to graceful delete rsList: %+v", ele)
 	m.rsList.add(ele)
 	return nil
 }
 
-func (m *GracefulTerminationManager) tryDeleteRs() {
-	for {
-		rsToDelete, _ := m.rsList.head()
-		glog.V(5).Infof("Trying to delete rs")
-		if rsToDelete == nil || rsToDelete.ProcessAt.After(time.Now()) {
-			break
+func (m *GracefulTerminationManager) deleteRsFunc(rsToDelete *listItem) (bool, error) {
+	glog.Infof("Trying to delete rs: %s", rsToDelete.String())
+	rss, err := m.ipvs.GetRealServers(rsToDelete.VirtualServer)
+	if err != nil {
+		return false, err
+	}
+	for _, rs := range rss {
+		if rsToDelete.RealServer.Equal(rs) {
+			if rs.ActiveConn != 0 {
+				return false, nil
+			}
+			glog.Infof("Deleting rs: %s", rsToDelete.String())
+			err := m.ipvs.DeleteRealServer(rsToDelete.VirtualServer, rs)
+			if err != nil {
+				return false, fmt.Errorf("Delete destination %q err: %v", rs.String(), err)
+			}
+			return true, nil
 		}
+	}
+	return false, fmt.Errorf("Failed to delete rs %q, can't find the real server", rsToDelete.String())
+}
 
-		glog.V(5).Infof("Deleting rs: %s", rsToDelete.String())
-		err := m.ipvs.DeleteRealServer(rsToDelete.VirtualServer, rsToDelete.RealServer)
-		if err != nil {
-			glog.Errorf("Failed to delete destination: %v, error: %v", rsToDelete.RealServer, err)
-		}
-		if !m.rsList.remove(rsToDelete) {
-			glog.Errorf("Failed to pop out rsList.")
-		}
+func (m *GracefulTerminationManager) tryDeleteRs() {
+	if !m.rsList.flushList(m.deleteRsFunc) {
+		glog.Errorf("Try flush graceful termination list err")
 	}
 }
 
@@ -212,14 +215,7 @@ func (m *GracefulTerminationManager) Run() {
 			continue
 		}
 		for _, rs := range rss {
-			if rs.Weight == 0 {
-				ele := &listItem{
-					VirtualServer: vs,
-					RealServer:    rs,
-					ProcessAt:     time.Now().Add(rsGracefulDeletePeriod),
-				}
-				m.rsList.add(ele)
-			}
+			m.GracefulDeleteRS(vs, rs)
 		}
 	}
 

pkg/util/ipvs/ipvs.go

@@ -93,9 +93,11 @@ func (svc *VirtualServer) String() string {
 
 // RealServer is an user-oriented definition of an IPVS real server in its entirety.
 type RealServer struct {
-	Address net.IP
-	Port    uint16
-	Weight  int
+	Address      net.IP
+	Port         uint16
+	Weight       int
+	ActiveConn   int
+	InactiveConn int
 }
 
 func (rs *RealServer) String() string {

pkg/util/ipvs/ipvs_linux.go

@@ -215,9 +215,11 @@ func toRealServer(dst *libipvs.Destination) (*RealServer, error) {
 		return nil, errors.New("ipvs destination should not be empty")
 	}
 	return &RealServer{
-		Address: dst.Address,
-		Port:    dst.Port,
-		Weight:  dst.Weight,
+		Address:      dst.Address,
+		Port:         dst.Port,
+		Weight:       dst.Weight,
+		ActiveConn:   dst.ActiveConnections,
+		InactiveConn: dst.InactiveConnections,
 	}, nil
 }
 

pkg/util/ipvs/testing/fake_test.go

@@ -124,9 +124,9 @@ func TestRealServer(t *testing.T) {
 		Protocol: string("TCP"),
 	}
 	rss := []*utilipvs.RealServer{
-		{net.ParseIP("172.16.2.1"), 8080, 1},
-		{net.ParseIP("172.16.2.2"), 8080, 2},
-		{net.ParseIP("172.16.2.3"), 8080, 3},
+		{Address: net.ParseIP("172.16.2.1"), Port: 8080, Weight: 1},
+		{Address: net.ParseIP("172.16.2.2"), Port: 8080, Weight: 2},
+		{Address: net.ParseIP("172.16.2.3"), Port: 8080, Weight: 3},
 	}
 	err := fake.AddVirtualServer(vs)
 	if err != nil {