adjusting maxVolumeCount if volume server changes it

weed-fs/src/pkg/replication/volume_growth.go

@@ -63,10 +63,12 @@ func (vg *VolumeGrowth) GrowByCountAndType(count int, repType storage.Replicatio
 			if ret {
 				var servers []*topology.DataNode
 				for _, n := range picked {
+					if n.FreeSpace() > 0 {
 						if ok, server := n.ReserveOneVolume(rand.Intn(n.FreeSpace()), vid); ok {
 							servers = append(servers, server)
 						}
 					}
+				}
 				if len(servers) == 2 {
 					vg.grow(topo, vid, repType, servers[0], servers[1])
 				}
@@ -80,10 +82,12 @@ func (vg *VolumeGrowth) GrowByCountAndType(count int, repType storage.Replicatio
 			if ret {
 				var servers []*topology.DataNode
 				for _, n := range picked {
+					if n.FreeSpace() > 0 {
 						if ok, server := n.ReserveOneVolume(rand.Intn(n.FreeSpace()), vid); ok {
 							servers = append(servers, server)
 						}
 					}
+				}
 				if len(servers) == 3 {
 					vg.grow(topo, vid, repType, servers[0], servers[1], servers[2])
 				}

weed-fs/src/pkg/topology/rack.go

@@ -28,6 +28,7 @@ func (r *Rack) GetOrCreateDataNode(ip string, port int, publicUrl string, maxVol
 	for _, c := range r.Children() {
 		dn := c.(*DataNode)
 		if dn.MatchLocation(ip, port) {
+			dn.NodeImpl.UpAdjustMaxVolumeCountDelta(maxVolumeCount - dn.maxVolumeCount)
 			return dn
 		}
 	}

weed-fs/src/pkg/topology/topology.go

@@ -42,14 +42,17 @@ func (t *Topology) RandomlyReserveOneVolume() (bool, *DataNode, *storage.VolumeI
 	return ret, node, &vid
 }
 
-func (t *Topology) RandomlyReserveOneVolumeExcept(except []Node) (bool, *DataNode, storage.VolumeId) {
+func (t *Topology) RandomlyReserveOneVolumeExcept(except []Node) (bool, *DataNode, *storage.VolumeId) {
 	freeSpace := t.FreeSpace()
 	for _, node := range except {
 		freeSpace -= node.FreeSpace()
 	}
+	if freeSpace <= 0 {
+		return false, nil, nil
+	}
 	vid := t.NextVolumeId()
 	ret, node := t.ReserveOneVolume(rand.Intn(freeSpace), vid)
-	return ret, node, vid
+	return ret, node, &vid
 }
 
 func (t *Topology) NextVolumeId() storage.VolumeId {