seaweedfs/weed/topology/node.go
2021-07-01 01:21:14 -07:00

266 lines
7.4 KiB
Go

package topology
import (
"errors"
"github.com/chrislusf/seaweedfs/weed/glog"
"github.com/chrislusf/seaweedfs/weed/storage/erasure_coding"
"github.com/chrislusf/seaweedfs/weed/storage/needle"
"github.com/chrislusf/seaweedfs/weed/storage/types"
"math/rand"
"strings"
"sync"
)
type NodeId string
type Node interface {
Id() NodeId
String() string
AvailableSpaceFor(option *VolumeGrowOption) int64
ReserveOneVolume(r int64, option *VolumeGrowOption) (*DataNode, error)
UpAdjustDiskUsageDelta(deltaDiskUsages *DiskUsages)
UpAdjustMaxVolumeId(vid needle.VolumeId)
GetDiskUsages() *DiskUsages
GetMaxVolumeId() needle.VolumeId
SetParent(Node)
LinkChildNode(node Node)
UnlinkChildNode(nodeId NodeId)
CollectDeadNodeAndFullVolumes(freshThreshHold int64, volumeSizeLimit uint64, growThreshold float64)
IsDataNode() bool
IsRack() bool
IsDataCenter() bool
Children() []Node
Parent() Node
GetValue() interface{} //get reference to the topology,dc,rack,datanode
}
type NodeImpl struct {
diskUsages *DiskUsages
id NodeId
parent Node
sync.RWMutex // lock children
children map[NodeId]Node
maxVolumeId needle.VolumeId
//for rack, data center, topology
nodeType string
value interface{}
}
func (n *NodeImpl) GetDiskUsages() *DiskUsages {
return n.diskUsages
}
// the first node must satisfy filterFirstNodeFn(), the rest nodes must have one free slot
func (n *NodeImpl) PickNodesByWeight(numberOfNodes int, option *VolumeGrowOption, filterFirstNodeFn func(dn Node) error) (firstNode Node, restNodes []Node, err error) {
var totalWeights int64
var errs []string
n.RLock()
candidates := make([]Node, 0, len(n.children))
candidatesWeights := make([]int64, 0, len(n.children))
//pick nodes which has enough free volumes as candidates, and use free volumes number as node weight.
for _, node := range n.children {
if node.AvailableSpaceFor(option) <= 0 {
continue
}
totalWeights += node.AvailableSpaceFor(option)
candidates = append(candidates, node)
candidatesWeights = append(candidatesWeights, node.AvailableSpaceFor(option))
}
n.RUnlock()
if len(candidates) < numberOfNodes {
glog.V(0).Infoln(n.Id(), "failed to pick", numberOfNodes, "from ", len(candidates), "node candidates")
return nil, nil, errors.New("No enough data node found!")
}
//pick nodes randomly by weights, the node picked earlier has higher final weights
sortedCandidates := make([]Node, 0, len(candidates))
for i := 0; i < len(candidates); i++ {
weightsInterval := rand.Int63n(totalWeights)
lastWeights := int64(0)
for k, weights := range candidatesWeights {
if (weightsInterval >= lastWeights) && (weightsInterval < lastWeights+weights) {
sortedCandidates = append(sortedCandidates, candidates[k])
candidatesWeights[k] = 0
totalWeights -= weights
break
}
lastWeights += weights
}
}
restNodes = make([]Node, 0, numberOfNodes-1)
ret := false
n.RLock()
for k, node := range sortedCandidates {
if err := filterFirstNodeFn(node); err == nil {
firstNode = node
if k >= numberOfNodes-1 {
restNodes = sortedCandidates[:numberOfNodes-1]
} else {
restNodes = append(restNodes, sortedCandidates[:k]...)
restNodes = append(restNodes, sortedCandidates[k+1:numberOfNodes]...)
}
ret = true
break
} else {
errs = append(errs, string(node.Id())+":"+err.Error())
}
}
n.RUnlock()
if !ret {
return nil, nil, errors.New("No matching data node found! \n" + strings.Join(errs, "\n"))
}
return
}
func (n *NodeImpl) IsDataNode() bool {
return n.nodeType == "DataNode"
}
func (n *NodeImpl) IsRack() bool {
return n.nodeType == "Rack"
}
func (n *NodeImpl) IsDataCenter() bool {
return n.nodeType == "DataCenter"
}
func (n *NodeImpl) String() string {
if n.parent != nil {
return n.parent.String() + ":" + string(n.id)
}
return string(n.id)
}
func (n *NodeImpl) Id() NodeId {
return n.id
}
func (n *NodeImpl) getOrCreateDisk(diskType types.DiskType) *DiskUsageCounts {
return n.diskUsages.getOrCreateDisk(diskType)
}
func (n *NodeImpl) AvailableSpaceFor(option *VolumeGrowOption) int64 {
t := n.getOrCreateDisk(option.DiskType)
freeVolumeSlotCount := t.maxVolumeCount + t.remoteVolumeCount - t.volumeCount
if t.ecShardCount > 0 {
freeVolumeSlotCount = freeVolumeSlotCount - t.ecShardCount/erasure_coding.DataShardsCount - 1
}
return freeVolumeSlotCount
}
func (n *NodeImpl) SetParent(node Node) {
n.parent = node
}
func (n *NodeImpl) Children() (ret []Node) {
n.RLock()
defer n.RUnlock()
for _, c := range n.children {
ret = append(ret, c)
}
return ret
}
func (n *NodeImpl) Parent() Node {
return n.parent
}
func (n *NodeImpl) GetValue() interface{} {
return n.value
}
func (n *NodeImpl) ReserveOneVolume(r int64, option *VolumeGrowOption) (assignedNode *DataNode, err error) {
n.RLock()
defer n.RUnlock()
for _, node := range n.children {
freeSpace := node.AvailableSpaceFor(option)
// fmt.Println("r =", r, ", node =", node, ", freeSpace =", freeSpace)
if freeSpace <= 0 {
continue
}
if r >= freeSpace {
r -= freeSpace
} else {
if node.IsDataNode() && node.AvailableSpaceFor(option) > 0 {
// fmt.Println("vid =", vid, " assigned to node =", node, ", freeSpace =", node.FreeSpace())
return node.(*DataNode), nil
}
assignedNode, err = node.ReserveOneVolume(r, option)
if err == nil {
return
}
}
}
return nil, errors.New("No free volume slot found!")
}
func (n *NodeImpl) UpAdjustDiskUsageDelta(deltaDiskUsages *DiskUsages) { //can be negative
for diskType, diskUsage := range deltaDiskUsages.usages {
existingDisk := n.getOrCreateDisk(diskType)
existingDisk.addDiskUsageCounts(diskUsage)
}
if n.parent != nil {
n.parent.UpAdjustDiskUsageDelta(deltaDiskUsages)
}
}
func (n *NodeImpl) UpAdjustMaxVolumeId(vid needle.VolumeId) { //can be negative
if n.maxVolumeId < vid {
n.maxVolumeId = vid
if n.parent != nil {
n.parent.UpAdjustMaxVolumeId(vid)
}
}
}
func (n *NodeImpl) GetMaxVolumeId() needle.VolumeId {
return n.maxVolumeId
}
func (n *NodeImpl) LinkChildNode(node Node) {
n.Lock()
defer n.Unlock()
n.doLinkChildNode(node)
}
func (n *NodeImpl) doLinkChildNode(node Node) {
if n.children[node.Id()] == nil {
n.children[node.Id()] = node
n.UpAdjustDiskUsageDelta(node.GetDiskUsages())
n.UpAdjustMaxVolumeId(node.GetMaxVolumeId())
node.SetParent(n)
glog.V(0).Infoln(n, "adds child", node.Id())
}
}
func (n *NodeImpl) UnlinkChildNode(nodeId NodeId) {
n.Lock()
defer n.Unlock()
node := n.children[nodeId]
if node != nil {
node.SetParent(nil)
delete(n.children, node.Id())
n.UpAdjustDiskUsageDelta(node.GetDiskUsages().negative())
glog.V(0).Infoln(n, "removes", node.Id())
}
}
func (n *NodeImpl) CollectDeadNodeAndFullVolumes(freshThreshHold int64, volumeSizeLimit uint64, growThreshold float64) {
if n.IsRack() {
for _, c := range n.Children() {
dn := c.(*DataNode) //can not cast n to DataNode
for _, v := range dn.GetVolumes() {
if v.Size >= volumeSizeLimit {
//fmt.Println("volume",v.Id,"size",v.Size,">",volumeSizeLimit)
n.GetTopology().chanFullVolumes <- v
} else if float64(v.Size) > float64(volumeSizeLimit)*growThreshold {
n.GetTopology().chanCrowdedVolumes <- v
}
}
}
} else {
for _, c := range n.Children() {
c.CollectDeadNodeAndFullVolumes(freshThreshHold, volumeSizeLimit, growThreshold)
}
}
}
func (n *NodeImpl) GetTopology() *Topology {
var p Node
p = n
for p.Parent() != nil {
p = p.Parent()
}
return p.GetValue().(*Topology)
}