Fix EC shard count logic

This fixes the calculation of the amount of EC shards a node holds.
Previously a global counter was increased, but also used inside the
loop to apply disk usage deltas. This led to wrong absolute numbers.
The fix is to apply only deltas of single EC shards per iteration.

weed/topology/data_node_ec.go

@@ -25,7 +25,7 @@ func (dn *DataNode) UpdateEcShards(actualShards []*erasure_coding.EcVolumeInfo)
 
 	existingEcShards := dn.GetEcShards()
 
-	// found out the newShards and deletedShards
+	// find out the newShards and deletedShards
 	var newShardCount, deletedShardCount int
 	for _, ecShards := range existingEcShards {
 
@@ -56,20 +56,19 @@ func (dn *DataNode) UpdateEcShards(actualShards []*erasure_coding.EcVolumeInfo)
 		disk.UpAdjustDiskUsageDelta(deltaDiskUsages)
 
 	}
+
 	for _, ecShards := range actualShards {
+		if dn.hasEcShards(ecShards.VolumeId) {
+			continue
+		}
+
+		newShards = append(newShards, ecShards)
 
 		disk := dn.getOrCreateDisk(ecShards.DiskType)
 		deltaDiskUsages := newDiskUsages()
 		deltaDiskUsage := deltaDiskUsages.getOrCreateDisk(types.ToDiskType(ecShards.DiskType))
-
-		if !dn.hasEcShards(ecShards.VolumeId) {
-			newShards = append(newShards, ecShards)
-			newShardCount += ecShards.ShardIdCount()
-		}
-
-		deltaDiskUsage.ecShardCount = int64(newShardCount)
+		deltaDiskUsage.ecShardCount = int64(ecShards.ShardIdCount())
 		disk.UpAdjustDiskUsageDelta(deltaDiskUsages)
-
 	}
 
 	if len(newShards) > 0 || len(deletedShards) > 0 {