4 files changed, 77 insertions, 0 deletions
diff --git a/weed/server/master_grpc_server.go b/weed/server/master_grpc_server.go
index bc6463251..69bd56df0 100644
--- a/weed/server/master_grpc_server.go
+++ b/weed/server/master_grpc_server.go
@@ -103,6 +103,13 @@ func (ms *MasterServer) SendHeartbeat(stream master_pb.Seaweed_SendHeartbeatServ
 			}
 		}
 
+		if len(heartbeat.NewEcShards) > 0 || len(heartbeat.DeletedEcShards) > 0 {
+			// TODO send out the delta
+
+			// update master internal volume layouts
+			t.IncrementalSyncDataNodeEcShards(heartbeat.NewEcShards, heartbeat.DeletedEcShards, dn)
+		}
+
 		if len(heartbeat.EcShards) > 0 {
 			glog.V(0).Infof("master recieved ec shards from %s: %+v", dn.Url(), heartbeat.EcShards)
 			newShards, deletedShards := t.SyncDataNodeEcShards(heartbeat.EcShards, dn)
diff --git a/weed/storage/erasure_coding/ec_volume_info.go b/weed/storage/erasure_coding/ec_volume_info.go
index ef8cc4ed4..48f4713d9 100644
--- a/weed/storage/erasure_coding/ec_volume_info.go
+++ b/weed/storage/erasure_coding/ec_volume_info.go
@@ -91,3 +91,7 @@ func (b ShardBits) ShardIdCount() (count int) {
 func (b ShardBits) Minus(other ShardBits) (ShardBits) {
 	return b &^ other
 }
+
+func (b ShardBits) Plus(other ShardBits) (ShardBits) {
+	return b | other
+}
diff --git a/weed/topology/data_node_ec.go b/weed/topology/data_node_ec.go
index 63c8f2127..95635331b 100644
--- a/weed/topology/data_node_ec.go
+++ b/weed/topology/data_node_ec.go
@@ -55,3 +55,40 @@ func (dn *DataNode) UpdateEcShards(actualShards []*erasure_coding.EcVolumeInfo)
 
 	return
 }
+
+func (dn *DataNode) DeltaUpdateEcShards(newShards, deletedShards []*erasure_coding.EcVolumeInfo) {
+
+	for _, newShard := range newShards {
+		dn.AddOrUpdateEcShard(newShard)
+	}
+
+	for _, deletedShard := range deletedShards {
+		dn.DeleteEcShard(deletedShard)
+	}
+
+}
+
+func (dn *DataNode) AddOrUpdateEcShard(s *erasure_coding.EcVolumeInfo) {
+	dn.ecShardsLock.Lock()
+	defer dn.ecShardsLock.Unlock()
+
+	if existing, ok := dn.ecShards[s.VolumeId]; !ok {
+		dn.ecShards[s.VolumeId] = s
+	} else {
+		existing.ShardBits = existing.ShardBits.Plus(s.ShardBits)
+	}
+
+}
+
+func (dn *DataNode) DeleteEcShard(s *erasure_coding.EcVolumeInfo) {
+	dn.ecShardsLock.Lock()
+	defer dn.ecShardsLock.Unlock()
+
+	if existing, ok := dn.ecShards[s.VolumeId]; ok {
+		existing.ShardBits = existing.ShardBits.Minus(s.ShardBits)
+		if existing.ShardBits.ShardIdCount() == 0 {
+			delete(dn.ecShards, s.VolumeId)
+		}
+	}
+
+}
diff --git a/weed/topology/topology_ec.go b/weed/topology/topology_ec.go
index 050a0b901..61de86753 100644
--- a/weed/topology/topology_ec.go
+++ b/weed/topology/topology_ec.go
@@ -33,6 +33,35 @@ func (t *Topology) SyncDataNodeEcShards(shardInfos []*master_pb.VolumeEcShardInf
 	return
 }
 
+func (t *Topology) IncrementalSyncDataNodeEcShards(newEcShards, deletedEcShards []*master_pb.VolumeEcShardInformationMessage, dn *DataNode) {
+	// convert into in memory struct storage.VolumeInfo
+	var newShards, deletedShards []*erasure_coding.EcVolumeInfo
+	for _, shardInfo := range newEcShards {
+		newShards = append(newShards,
+			erasure_coding.NewEcVolumeInfo(
+				shardInfo.Collection,
+				needle.VolumeId(shardInfo.Id),
+				erasure_coding.ShardBits(shardInfo.EcIndexBits)))
+	}
+	for _, shardInfo := range deletedEcShards {
+		deletedShards = append(deletedShards,
+			erasure_coding.NewEcVolumeInfo(
+				shardInfo.Collection,
+				needle.VolumeId(shardInfo.Id),
+				erasure_coding.ShardBits(shardInfo.EcIndexBits)))
+	}
+
+	dn.DeltaUpdateEcShards(newShards, deletedShards)
+
+	for _, v := range newShards {
+		t.RegisterEcShards(v, dn)
+	}
+	for _, v := range deletedShards {
+		t.UnRegisterEcShards(v, dn)
+	}
+	return
+}
+
 func NewEcShardLocations(collection string) *EcShardLocations {
 	return &EcShardLocations{
 		Collection: collection,