feature: limit the number which download from supernode for one task

Signed-off-by: Starnop <starnop@163.com>

supernode/config/config.go

@@ -144,7 +144,7 @@ type BaseProperties struct {
 	// PeerDownLimit is the download limit of a peer. When a peer starts to download a file/image,
 	// it will download file/image in the form of pieces. PeerDownLimit mean that a peer can only
 	// stand starting PeerDownLimit concurrent downloading tasks.
-	// default: 4
+	// default: 5
 	PeerDownLimit int `yaml:"peerDownLimit"`
 
 	// When dfget node starts to play a role of peer, it will provide services for other peers

supernode/daemon/mgr/progress/progress_delete.go

@@ -24,6 +24,7 @@ import (
 
 // DeleteTaskID deletes the super progress with specified taskID.
 func (pm *Manager) DeleteTaskID(ctx context.Context, taskID string) (err error) {
+	pm.superLoad.remove(taskID)
 	return pm.superProgress.remove(taskID)
 }
 

supernode/daemon/mgr/progress/progress_manager.go

@@ -51,39 +51,47 @@ var _ mgr.ProgressMgr = &Manager{}
 // Manager is an implementation of the interface of ProgressMgr.
 type Manager struct {
 	// superProgress maintains the super progress.
-	// key:taskID,value:*superState
+	// key:taskID string, value:superState *superState
 	superProgress *stateSyncMap
 
 	// clientProgress maintains the client progress.
-	// key:CID,value:*clientState
+	// key:CID string, value:clientState *clientState
 	clientProgress *stateSyncMap
 
 	// peerProgress maintains the peer progress.
-	// key:PeerID,value:*peerState
+	// key:PeerID string, value:peerState *peerState
 	peerProgress *stateSyncMap
 
 	// pieceProgress maintains the information about
 	// which peers the piece currently exists on
-	// key:pieceNum@taskID,value:*pieceState
+	// key:pieceNum@taskID string, value:pieceState *pieceState
 	pieceProgress *stateSyncMap
 
 	// clientBlackInfo maintains the blacklist of the PID.
-	// key:srcPID,value:map[dstPID]*Atomic
+	// key:srcPID string, value:dstPIDMap map[dstPID]*Atomic
 	clientBlackInfo *syncmap.SyncMap
 
+	// superLoad maintains the load num downloaded from the supernode for each task.
+	// key:taskID string, value:superLoadState *superLoadState
+	superLoad *stateSyncMap
+
 	cfg *config.Config
 }
 
 // NewManager returns a new Manager.
 func NewManager(cfg *config.Config) (*Manager, error) {
-	return &Manager{
+	manager := &Manager{
 		cfg:             cfg,
 		superProgress:   newStateSyncMap(),
 		clientProgress:  newStateSyncMap(),
 		peerProgress:    newStateSyncMap(),
 		pieceProgress:   newStateSyncMap(),
 		clientBlackInfo: syncmap.NewSyncMap(),
-	}, nil
+		superLoad:       newStateSyncMap(),
+	}
+
+	manager.startMonitorSuperLoad()
+	return manager, nil
 }
 
 // InitProgress inits the correlation information between peers and pieces, etc.

supernode/daemon/mgr/progress/progress_state.go

@@ -17,6 +17,8 @@
 package progress
 
 import (
+	"time"
+
 	"github.com/dragonflyoss/Dragonfly/pkg/atomiccount"
 	"github.com/dragonflyoss/Dragonfly/pkg/syncmap"
 
@@ -61,6 +63,14 @@ type peerState struct {
 	serviceDownTime int64
 }
 
+type superLoadState struct {
+	// superLoad maintains the load num downloaded from the supernode for each task.
+	loadValue *atomiccount.AtomicInt
+
+	// loadModTime will record the time when the load be modified.
+	loadModTime time.Time
+}
+
 func newSuperState() *superState {
 	return &superState{
 		pieceBitSet: &bitset.BitSet{},
@@ -81,3 +91,10 @@ func newPeerState() *peerState {
 		serviceErrorCount: atomiccount.NewAtomicInt(0),
 	}
 }
+
+func newSuperLoadState() *superLoadState {
+	return &superLoadState{
+		loadValue:   atomiccount.NewAtomicInt(0),
+		loadModTime: time.Now(),
+	}
+}

supernode/daemon/mgr/progress/state_sync_map.go

@@ -23,7 +23,7 @@ import (
 	"github.com/pkg/errors"
 )
 
-// stateSyncMap is a thread-safe map.
+// stateSyncMap is a thread-safe map for progress state.
 type stateSyncMap struct {
 	*syncmap.SyncMap
 }
@@ -102,6 +102,20 @@ func (mmap *stateSyncMap) getAsPieceState(key string) (*pieceState, error) {
 	return nil, errors.Wrapf(errortypes.ErrConvertFailed, "key %s: %v", key, v)
 }
 
+// getAsSuperLoadState returns result as *superLoadState.
+// The ErrConvertFailed error will be returned if the assertion fails.
+func (mmap *stateSyncMap) getAsSuperLoadState(key string) (*superLoadState, error) {
+	v, err := mmap.get(key)
+	if err != nil {
+		return nil, errors.Wrapf(err, "key: %s", key)
+	}
+
+	if value, ok := v.(*superLoadState); ok {
+		return value, nil
+	}
+	return nil, errors.Wrapf(errortypes.ErrConvertFailed, "key %s: %v", key, v)
+}
+
 // remove deletes the key-value pair from the mmap.
 // The ErrEmptyValue error will be returned if the key is empty.
 // And the ErrDataNotFound error will be returned if the key cannot be found.

supernode/daemon/mgr/progress/superload_manager.go

@@ -0,0 +1,78 @@
+/*
+ * Copyright The Dragonfly Authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package progress
+
+import (
+	"context"
+	"time"
+
+	"github.com/dragonflyoss/Dragonfly/pkg/errortypes"
+)
+
+const (
+	// renewInterval is the interval time to check the superload.
+	renewInterval = 2 * time.Second
+
+	// renewDelayTime if the superload has not been changed after renewDelayTime, it should be renewed.
+	renewDelayTime = 30 * time.Second
+)
+
+// UpdateSuperLoad updates the superload of taskID by adding the delta.
+// The updated will be `false` if failed to do update operation.
+//
+// It's considered as a failure when then superload is greater than limit after adding delta.
+func (pm *Manager) UpdateSuperLoad(ctx context.Context, taskID string, delta, limit int32) (updated bool, err error) {
+	v, _ := pm.superLoad.LoadOrStore(taskID, newSuperLoadState())
+	loadState, ok := v.(*superLoadState)
+	if !ok {
+		return false, errortypes.ErrConvertFailed
+	}
+
+	if loadState.loadValue.Add(delta) > limit && limit > 0 {
+		loadState.loadValue.Add(-delta)
+		return false, nil
+	}
+	loadState.loadModTime = time.Now()
+
+	return true, nil
+}
+
+// startMonitorSuperLoad starts a new goroutine to check the superload periodically and
+// reset the superload to zero if there is no update for a long time for one task to
+// avoid being occupied when supernode doesn't receive the message from peers that downloading piece from supernode for a variety of reasons.
+//
+func (pm *Manager) startMonitorSuperLoad() {
+	go func() {
+		ticker := time.NewTicker(renewInterval)
+		for range ticker.C {
+			pm.renewSuperLoad()
+		}
+	}()
+}
+
+func (pm *Manager) renewSuperLoad() {
+	rangeFunc := func(key, value interface{}) bool {
+		if v, ok := value.(*superLoadState); ok {
+			if time.Since(v.loadModTime) > renewDelayTime {
+				v.loadValue.Set(0)
+			}
+		}
+		return true
+	}
+
+	pm.superLoad.Range(rangeFunc)
+}

supernode/daemon/mgr/progress_mgr.go

@@ -70,10 +70,10 @@ type ProgressMgr interface {
 	// GetPeerStateByPeerID gets peer state with specified peerID.
 	GetPeerStateByPeerID(ctx context.Context, peerID string) (peerState *PeerState, err error)
 
-	// UpdatePeerServiceDown do update operation when a peer server offline.
+	// UpdateSuperLoad updates the superload of taskID by adding the delta.
+	// The updated will be `false` if failed to do update operation.
 	//
-	// This function will update the service down time for the peerID.
-	// And the supernode will not dispatch tasks to this peer.
+	// It's considered as a failure when then superload is greater than limit after adding delta.
 	UpdatePeerServiceDown(ctx context.Context, peerID string) (err error)
 
 	// GetPeersByTaskID gets all peers info with specified taskID.
@@ -82,6 +82,11 @@ type ProgressMgr interface {
 	// GetBlackInfoByPeerID gets black info with specified peerID.
 	GetBlackInfoByPeerID(ctx context.Context, peerID string) (dstPIDMap *syncmap.SyncMap, err error)
 
+	// UpdateSuperLoad update the superLoad with delta.
+	//
+	// The value will be rolled back if it exceeds the limit after updated and returns false.
+	UpdateSuperLoad(ctx context.Context, taskID string, delta, limit int32) (updated bool, err error)
+
 	// DeleteTaskID deletes the super progress with specified taskID.
 	DeleteTaskID(ctx context.Context, taskID string) (err error)
 

supernode/daemon/mgr/scheduler/manager.go

@@ -172,6 +172,18 @@ func (sm *Manager) getPieceResults(ctx context.Context, taskID, clientID, peerID
 			continue
 		}
 
+		// We limit the number of simultaneous connections that supernode can accept for each task.
+		if sm.cfg.IsSuperPID(dstPID) {
+			updated, err := sm.progressMgr.UpdateSuperLoad(ctx, taskID, 1, int32(sm.cfg.PeerDownLimit))
+			if err != nil {
+				logrus.Warnf("failed to update super load taskID(%s) clientID(%s): %v", taskID, clientID, err)
+				continue
+			}
+			if !updated {
+				continue
+			}
+		}
+
 		if err := sm.progressMgr.UpdateClientProgress(ctx, taskID, clientID, dstPID, pieceNums[i], config.PieceRUNNING); err != nil {
 			logrus.Warnf("scheduler: failed to update client progress running for pieceNum(%d) taskID(%s) clientID(%s) dstPID(%s)", pieceNums[i], taskID, clientID, dstPID)
 			continue

supernode/daemon/mgr/task/manager.go

@@ -272,6 +272,15 @@ func (tm *Manager) UpdatePieceStatus(ctx context.Context, taskID, pieceRange str
 			pieceRange, taskID, pieceUpdateRequest.ClientID)
 	}
 
+	// when a peer success to download a piece from supernode,
+	// and the load of supernode for the taskID should be decremented by one.
+	if tm.cfg.IsSuperPID(pieceUpdateRequest.DstPID) {
+		_, err := tm.progressMgr.UpdateSuperLoad(ctx, taskID, -1, -1)
+		if err != nil {
+			logrus.Warnf("failed to update superLoad taskID(%s) clientID(%s): %v", taskID, pieceUpdateRequest.ClientID, err)
+		}
+	}
+
 	// get dfgetTask according to the CID
 	srcDfgetTask, err := tm.dfgetTaskMgr.Get(ctx, pieceUpdateRequest.ClientID, taskID)
 	if err != nil {

supernode/daemon/mgr/task/manager_util.go

@@ -345,6 +345,9 @@ func (tm *Manager) parseAvailablePeers(ctx context.Context, clientID string, tas
 	tm.metrics.scheduleDurationMilliSeconds.WithLabelValues(peer.IP.String()).Observe(timeutils.SinceInMilliseconds(startTime))
 	logrus.Debugf("get scheduler result length(%d) with taskID(%s) and clientID(%s)", len(pieceResult), task.ID, clientID)
 
+	if len(pieceResult) == 0 {
+		return false, nil, errortypes.ErrPeerWait
+	}
 	var pieceInfos []*types.PieceInfo
 	for _, v := range pieceResult {
 		logrus.Debugf("get scheduler result item: %+v with taskID(%s) and clientID(%s)", v, task.ID, clientID)