seaweedfs/weed/shell/command_volume_fix_replication.go
2019-04-17 22:04:49 -07:00

206 lines
6.3 KiB
Go

package shell
import (
"context"
"fmt"
"github.com/chrislusf/seaweedfs/weed/operation"
"github.com/chrislusf/seaweedfs/weed/pb/master_pb"
"github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb"
"github.com/chrislusf/seaweedfs/weed/storage"
"io"
"math/rand"
"sort"
)
func init() {
commands = append(commands, &commandVolumeFixReplication{})
}
type commandVolumeFixReplication struct {
}
func (c *commandVolumeFixReplication) Name() string {
return "volume.fix.replication"
}
func (c *commandVolumeFixReplication) Help() string {
return `add replicas to volumes that are missing replicas
This command file all under-replicated volumes, and find volume servers with free slots.
If the free slots satisfy the replication requirement, the volume content is copied over and mounted.
volume.fix.replication -n # do not take action
volume.fix.replication # actually copying the volume files and mount the volume
Note:
* each time this will only add back one replica for one volume id. If there are multiple replicas
are missing, e.g. multiple volume servers are new, you may need to run this multiple times.
* do not run this too quick within seconds, since the new volume replica may take a few seconds
to register itself to the master.
`
}
func (c *commandVolumeFixReplication) Do(args []string, commandEnv *commandEnv, writer io.Writer) (err error) {
takeAction := true
if len(args) > 0 && args[0] == "-n" {
takeAction = false
}
var resp *master_pb.VolumeListResponse
ctx := context.Background()
err = commandEnv.masterClient.WithClient(ctx, func(client master_pb.SeaweedClient) error {
resp, err = client.VolumeList(ctx, &master_pb.VolumeListRequest{})
return err
})
if err != nil {
return err
}
// find all volumes that needs replication
// collect all data nodes
replicatedVolumeLocations := make(map[uint32][]location)
replicatedVolumeInfo := make(map[uint32]*master_pb.VolumeInformationMessage)
var allLocations []location
for _, dc := range resp.TopologyInfo.DataCenterInfos {
for _, rack := range dc.RackInfos {
for _, dn := range rack.DataNodeInfos {
loc := newLocation(dc.Id, rack.Id, dn)
for _, v := range dn.VolumeInfos {
if v.ReplicaPlacement > 0 {
replicatedVolumeLocations[v.Id] = append(replicatedVolumeLocations[v.Id], loc)
replicatedVolumeInfo[v.Id] = v
}
}
allLocations = append(allLocations, loc)
}
}
}
// find all under replicated volumes
underReplicatedVolumeLocations := make(map[uint32][]location)
for vid, locations := range replicatedVolumeLocations {
volumeInfo := replicatedVolumeInfo[vid]
replicaPlacement, _ := storage.NewReplicaPlacementFromByte(byte(volumeInfo.ReplicaPlacement))
if replicaPlacement.GetCopyCount() > len(locations) {
underReplicatedVolumeLocations[vid] = locations
}
}
if len(underReplicatedVolumeLocations) == 0 {
return fmt.Errorf("no under replicated volumes")
}
if len(allLocations) == 0 {
return fmt.Errorf("no data nodes at all")
}
// find the most under populated data nodes
keepDataNodesSorted(allLocations)
for vid, locations := range underReplicatedVolumeLocations {
volumeInfo := replicatedVolumeInfo[vid]
replicaPlacement, _ := storage.NewReplicaPlacementFromByte(byte(volumeInfo.ReplicaPlacement))
foundNewLocation := false
for _, dst := range allLocations {
// check whether data nodes satisfy the constraints
if dst.dataNode.FreeVolumeCount > 0 && satisfyReplicaPlacement(replicaPlacement, locations, dst) {
// ask the volume server to replicate the volume
sourceNodes := underReplicatedVolumeLocations[vid]
sourceNode := sourceNodes[rand.Intn(len(sourceNodes))]
foundNewLocation = true
fmt.Fprintf(writer, "replicating volume %d %s from %s to dataNode %s ...\n", volumeInfo.Id, replicaPlacement, sourceNode.dataNode.Id, dst.dataNode.Id)
if !takeAction {
break
}
err := operation.WithVolumeServerClient(dst.dataNode.Id, commandEnv.option.GrpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
_, replicateErr := volumeServerClient.VolumeCopy(ctx, &volume_server_pb.VolumeCopyRequest{
VolumeId: volumeInfo.Id,
Collection: volumeInfo.Collection,
SourceDataNode: sourceNode.dataNode.Id,
})
return replicateErr
})
if err != nil {
return err
}
// adjust free volume count
dst.dataNode.FreeVolumeCount--
keepDataNodesSorted(allLocations)
break
}
}
if !foundNewLocation {
fmt.Fprintf(writer, "failed to place volume %d replica as %s, existing:%+v\n", volumeInfo.Id, replicaPlacement, locations)
}
}
return nil
}
func keepDataNodesSorted(dataNodes []location) {
sort.Slice(dataNodes, func(i, j int) bool {
return dataNodes[i].dataNode.FreeVolumeCount > dataNodes[j].dataNode.FreeVolumeCount
})
}
func satisfyReplicaPlacement(replicaPlacement *storage.ReplicaPlacement, existingLocations []location, possibleLocation location) bool {
existingDataCenters := make(map[string]bool)
existingRacks := make(map[string]bool)
existingDataNodes := make(map[string]bool)
for _, loc := range existingLocations {
existingDataCenters[loc.DataCenter()] = true
existingRacks[loc.Rack()] = true
existingDataNodes[loc.String()] = true
}
if replicaPlacement.DiffDataCenterCount >= len(existingDataCenters) {
// check dc, good if different from any existing data centers
_, found := existingDataCenters[possibleLocation.DataCenter()]
return !found
} else if replicaPlacement.DiffRackCount >= len(existingRacks) {
// check rack, good if different from any existing racks
_, found := existingRacks[possibleLocation.Rack()]
return !found
} else if replicaPlacement.SameRackCount >= len(existingDataNodes) {
// check data node, good if different from any existing data nodes
_, found := existingDataNodes[possibleLocation.String()]
return !found
}
return false
}
type location struct {
dc string
rack string
dataNode *master_pb.DataNodeInfo
}
func newLocation(dc, rack string, dataNode *master_pb.DataNodeInfo) location {
return location{
dc: dc,
rack: rack,
dataNode: dataNode,
}
}
func (l location) String() string {
return fmt.Sprintf("%s %s %s", l.dc, l.rack, l.dataNode.Id)
}
func (l location) Rack() string {
return fmt.Sprintf("%s %s", l.dc, l.rack)
}
func (l location) DataCenter() string {
return l.dc
}