seaweedfs/weed/shell/command_ec_rebuild.go
2019-09-02 11:28:40 +01:00

269 lines
8.2 KiB
Go

package shell
import (
"context"
"flag"
"fmt"
"io"
"github.com/joeslay/seaweedfs/weed/operation"
"github.com/joeslay/seaweedfs/weed/pb/volume_server_pb"
"github.com/joeslay/seaweedfs/weed/storage/erasure_coding"
"github.com/joeslay/seaweedfs/weed/storage/needle"
"google.golang.org/grpc"
)
func init() {
Commands = append(Commands, &commandEcRebuild{})
}
type commandEcRebuild struct {
}
func (c *commandEcRebuild) Name() string {
return "ec.rebuild"
}
func (c *commandEcRebuild) Help() string {
return `find and rebuild missing ec shards among volume servers
ec.rebuild [-c EACH_COLLECTION|<collection_name>] [-force]
Algorithm:
For each type of volume server (different max volume count limit){
for each collection {
rebuildEcVolumes()
}
}
func rebuildEcVolumes(){
idealWritableVolumes = totalWritableVolumes / numVolumeServers
for {
sort all volume servers ordered by the number of local writable volumes
pick the volume server A with the lowest number of writable volumes x
pick the volume server B with the highest number of writable volumes y
if y > idealWritableVolumes and x +1 <= idealWritableVolumes {
if B has a writable volume id v that A does not have {
move writable volume v from A to B
}
}
}
}
`
}
func (c *commandEcRebuild) Do(args []string, commandEnv *CommandEnv, writer io.Writer) (err error) {
fixCommand := flag.NewFlagSet(c.Name(), flag.ContinueOnError)
collection := fixCommand.String("collection", "EACH_COLLECTION", "collection name, or \"EACH_COLLECTION\" for each collection")
applyChanges := fixCommand.Bool("force", false, "apply the changes")
if err = fixCommand.Parse(args); err != nil {
return nil
}
// collect all ec nodes
allEcNodes, _, err := collectEcNodes(context.Background(), commandEnv, "")
if err != nil {
return err
}
if *collection == "EACH_COLLECTION" {
collections, err := ListCollectionNames(commandEnv, false, true)
if err != nil {
return err
}
fmt.Printf("rebuildEcVolumes collections %+v\n", len(collections))
for _, c := range collections {
fmt.Printf("rebuildEcVolumes collection %+v\n", c)
if err = rebuildEcVolumes(commandEnv, allEcNodes, c, writer, *applyChanges); err != nil {
return err
}
}
} else {
if err = rebuildEcVolumes(commandEnv, allEcNodes, *collection, writer, *applyChanges); err != nil {
return err
}
}
return nil
}
func rebuildEcVolumes(commandEnv *CommandEnv, allEcNodes []*EcNode, collection string, writer io.Writer, applyChanges bool) error {
ctx := context.Background()
fmt.Printf("rebuildEcVolumes %s\n", collection)
// collect vid => each shard locations, similar to ecShardMap in topology.go
ecShardMap := make(EcShardMap)
for _, ecNode := range allEcNodes {
ecShardMap.registerEcNode(ecNode, collection)
}
for vid, locations := range ecShardMap {
shardCount := locations.shardCount()
if shardCount == erasure_coding.TotalShardsCount {
continue
}
if shardCount < erasure_coding.DataShardsCount {
return fmt.Errorf("ec volume %d is unrepairable with %d shards\n", vid, shardCount)
}
sortEcNodes(allEcNodes)
if allEcNodes[0].freeEcSlot < erasure_coding.TotalShardsCount {
return fmt.Errorf("disk space is not enough")
}
if err := rebuildOneEcVolume(ctx, commandEnv, allEcNodes[0], collection, vid, locations, writer, applyChanges); err != nil {
return err
}
}
return nil
}
func rebuildOneEcVolume(ctx context.Context, commandEnv *CommandEnv, rebuilder *EcNode, collection string, volumeId needle.VolumeId, locations EcShardLocations, writer io.Writer, applyChanges bool) error {
fmt.Printf("rebuildOneEcVolume %s %d\n", collection, volumeId)
// collect shard files to rebuilder local disk
var generatedShardIds []uint32
copiedShardIds, _, err := prepareDataToRecover(ctx, commandEnv, rebuilder, collection, volumeId, locations, writer, applyChanges)
if err != nil {
return err
}
defer func() {
// clean up working files
// ask the rebuilder to delete the copied shards
err = sourceServerDeleteEcShards(ctx, commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id, copiedShardIds)
if err != nil {
fmt.Fprintf(writer, "%s delete copied ec shards %s %d.%v\n", rebuilder.info.Id, collection, volumeId, copiedShardIds)
}
}()
if !applyChanges {
return nil
}
// generate ec shards, and maybe ecx file
generatedShardIds, err = generateMissingShards(ctx, commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id)
if err != nil {
return err
}
// mount the generated shards
err = mountEcShards(ctx, commandEnv.option.GrpcDialOption, collection, volumeId, rebuilder.info.Id, generatedShardIds)
if err != nil {
return err
}
rebuilder.addEcVolumeShards(volumeId, collection, generatedShardIds)
return nil
}
func generateMissingShards(ctx context.Context, grpcDialOption grpc.DialOption,
collection string, volumeId needle.VolumeId, sourceLocation string) (rebuiltShardIds []uint32, err error) {
err = operation.WithVolumeServerClient(sourceLocation, grpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
resp, rebultErr := volumeServerClient.VolumeEcShardsRebuild(ctx, &volume_server_pb.VolumeEcShardsRebuildRequest{
VolumeId: uint32(volumeId),
Collection: collection,
})
if rebultErr == nil {
rebuiltShardIds = resp.RebuiltShardIds
}
return rebultErr
})
return
}
func prepareDataToRecover(ctx context.Context, commandEnv *CommandEnv, rebuilder *EcNode, collection string, volumeId needle.VolumeId, locations EcShardLocations, writer io.Writer, applyBalancing bool) (copiedShardIds []uint32, localShardIds []uint32, err error) {
needEcxFile := true
var localShardBits erasure_coding.ShardBits
for _, ecShardInfo := range rebuilder.info.EcShardInfos {
if ecShardInfo.Collection == collection && needle.VolumeId(ecShardInfo.Id) == volumeId {
needEcxFile = false
localShardBits = erasure_coding.ShardBits(ecShardInfo.EcIndexBits)
}
}
for shardId, ecNodes := range locations {
if len(ecNodes) == 0 {
fmt.Fprintf(writer, "missing shard %d.%d\n", volumeId, shardId)
continue
}
if localShardBits.HasShardId(erasure_coding.ShardId(shardId)) {
localShardIds = append(localShardIds, uint32(shardId))
fmt.Fprintf(writer, "use existing shard %d.%d\n", volumeId, shardId)
continue
}
var copyErr error
if applyBalancing {
copyErr = operation.WithVolumeServerClient(rebuilder.info.Id, commandEnv.option.GrpcDialOption, func(volumeServerClient volume_server_pb.VolumeServerClient) error {
_, copyErr := volumeServerClient.VolumeEcShardsCopy(ctx, &volume_server_pb.VolumeEcShardsCopyRequest{
VolumeId: uint32(volumeId),
Collection: collection,
ShardIds: []uint32{uint32(shardId)},
CopyEcxFile: needEcxFile,
SourceDataNode: ecNodes[0].info.Id,
})
return copyErr
})
if copyErr == nil && needEcxFile {
needEcxFile = false
}
}
if copyErr != nil {
fmt.Fprintf(writer, "%s failed to copy %d.%d from %s: %v\n", rebuilder.info.Id, volumeId, shardId, ecNodes[0].info.Id, copyErr)
} else {
fmt.Fprintf(writer, "%s copied %d.%d from %s\n", rebuilder.info.Id, volumeId, shardId, ecNodes[0].info.Id)
copiedShardIds = append(copiedShardIds, uint32(shardId))
}
}
if len(copiedShardIds)+len(localShardIds) >= erasure_coding.DataShardsCount {
return copiedShardIds, localShardIds, nil
}
return nil, nil, fmt.Errorf("%d shards are not enough to recover volume %d", len(copiedShardIds)+len(localShardIds), volumeId)
}
type EcShardMap map[needle.VolumeId]EcShardLocations
type EcShardLocations [][]*EcNode
func (ecShardMap EcShardMap) registerEcNode(ecNode *EcNode, collection string) {
for _, shardInfo := range ecNode.info.EcShardInfos {
if shardInfo.Collection == collection {
existing, found := ecShardMap[needle.VolumeId(shardInfo.Id)]
if !found {
existing = make([][]*EcNode, erasure_coding.TotalShardsCount)
ecShardMap[needle.VolumeId(shardInfo.Id)] = existing
}
for _, shardId := range erasure_coding.ShardBits(shardInfo.EcIndexBits).ShardIds() {
existing[shardId] = append(existing[shardId], ecNode)
}
}
}
}
func (ecShardLocations EcShardLocations) shardCount() (count int) {
for _, locations := range ecShardLocations {
if len(locations) > 0 {
count++
}
}
return
}