package weed_server import ( "context" "fmt" "io" "math" "os" "github.com/chrislusf/seaweedfs/weed/glog" "github.com/chrislusf/seaweedfs/weed/operation" "github.com/chrislusf/seaweedfs/weed/pb/volume_server_pb" "github.com/chrislusf/seaweedfs/weed/storage" "github.com/chrislusf/seaweedfs/weed/storage/erasure_coding" "github.com/chrislusf/seaweedfs/weed/storage/needle" ) /* Steps to apply erasure coding to .dat .idx files 0. ensure the volume is readonly 1. client call VolumeEcShardsGenerate to generate the .ecx and .ec01~.ec14 files 2. client ask master for possible servers to hold the ec files, at least 4 servers 3. client call VolumeEcShardsCopy on above target servers to copy ec files from the source server 4. target servers report the new ec files to the master 5. master stores vid -> [14]*DataNode 6. client checks master. If all 14 slices are ready, delete the original .idx, .idx files */ // VolumeEcShardsGenerate generates the .ecx and .ec01 ~ .ec14 files func (vs *VolumeServer) VolumeEcShardsGenerate(ctx context.Context, req *volume_server_pb.VolumeEcShardsGenerateRequest) (*volume_server_pb.VolumeEcShardsGenerateResponse, error) { v := vs.store.GetVolume(needle.VolumeId(req.VolumeId)) if v == nil { return nil, fmt.Errorf("volume %d not found", req.VolumeId) } baseFileName := v.FileName() if v.Collection != req.Collection { return nil, fmt.Errorf("existing collection:%v unexpected input: %v", v.Collection, req.Collection) } // write .ecx file if err := erasure_coding.WriteSortedEcxFile(baseFileName); err != nil { return nil, fmt.Errorf("WriteSortedEcxFile %s: %v", baseFileName, err) } // write .ec01 ~ .ec14 files if err := erasure_coding.WriteEcFiles(baseFileName); err != nil { return nil, fmt.Errorf("WriteEcFiles %s: %v", baseFileName, err) } return &volume_server_pb.VolumeEcShardsGenerateResponse{}, nil } // VolumeEcShardsCopy copy the .ecx and some ec data slices func (vs *VolumeServer) VolumeEcShardsCopy(ctx context.Context, req *volume_server_pb.VolumeEcShardsCopyRequest) (*volume_server_pb.VolumeEcShardsCopyResponse, error) { location := vs.store.FindFreeLocation() if location == nil { return nil, fmt.Errorf("no space left") } baseFileName := storage.VolumeFileName(req.Collection, location.Directory, int(req.VolumeId)) err := operation.WithVolumeServerClient(req.SourceDataNode, vs.grpcDialOption, func(client volume_server_pb.VolumeServerClient) error { // copy ecx file if err := vs.doCopyFile(ctx, client, req.VolumeId, math.MaxUint32, math.MaxInt64, baseFileName, ".ecx"); err != nil { return err } // copy ec data slices for _, shardId := range req.ShardIds { if err := vs.doCopyFile(ctx, client, req.VolumeId, math.MaxUint32, math.MaxInt64, baseFileName, erasure_coding.ToExt(int(shardId))); err != nil { return err } } return nil }) if err != nil { return nil, fmt.Errorf("VolumeEcShardsCopy volume %d: %v", req.VolumeId, err) } return &volume_server_pb.VolumeEcShardsCopyResponse{}, nil } // VolumeEcShardsDelete local delete the .ecx and some ec data slices if not needed, assuming current server has the source volume func (vs *VolumeServer) VolumeEcShardsDelete(ctx context.Context, req *volume_server_pb.VolumeEcShardsDeleteRequest) (*volume_server_pb.VolumeEcShardsDeleteResponse, error) { v := vs.store.GetVolume(needle.VolumeId(req.VolumeId)) if v == nil { return nil, fmt.Errorf("volume %d not found", req.VolumeId) } baseFileName := v.FileName() for _, shardId := range req.ShardIds { if err := os.Remove(baseFileName + erasure_coding.ToExt(int(shardId))); err != nil { return nil, err } } if req.ShouldDeleteEcx { if err := os.Remove(baseFileName + ".ecx"); err != nil { return nil, err } } return &volume_server_pb.VolumeEcShardsDeleteResponse{}, nil } func (vs *VolumeServer) VolumeEcShardsMount(ctx context.Context, req *volume_server_pb.VolumeEcShardsMountRequest) (*volume_server_pb.VolumeEcShardsMountResponse, error) { for _, shardId := range req.ShardIds { err := vs.store.MountEcShards(req.Collection, needle.VolumeId(req.VolumeId), erasure_coding.ShardId(shardId)) if err != nil { glog.Errorf("ec shard mount %v: %v", req, err) } else { glog.V(2).Infof("ec shard mount %v", req) } if err != nil { return nil, fmt.Errorf("mount %d.%d: %v", req.VolumeId, shardId, err) } } return &volume_server_pb.VolumeEcShardsMountResponse{}, nil } func (vs *VolumeServer) VolumeEcShardsUnmount(ctx context.Context, req *volume_server_pb.VolumeEcShardsUnmountRequest) (*volume_server_pb.VolumeEcShardsUnmountResponse, error) { for _, shardId := range req.ShardIds { err := vs.store.UnmountEcShards(needle.VolumeId(req.VolumeId), erasure_coding.ShardId(shardId)) if err != nil { glog.Errorf("ec shard unmount %v: %v", req, err) } else { glog.V(2).Infof("ec shard unmount %v", req) } if err != nil { return nil, fmt.Errorf("unmount %d.%d: %v", req.VolumeId, shardId, err) } } return &volume_server_pb.VolumeEcShardsUnmountResponse{}, nil } func (vs *VolumeServer) VolumeEcShardRead(req *volume_server_pb.VolumeEcShardReadRequest, stream volume_server_pb.VolumeServer_VolumeEcShardReadServer) error { ecVolume, found := vs.store.FindEcVolume(needle.VolumeId(req.VolumeId)) if !found { return fmt.Errorf("not found ec volume id %d", req.VolumeId) } ecShard, found := ecVolume.FindEcVolumeShard(erasure_coding.ShardId(req.ShardId)) if !found { return fmt.Errorf("not found ec shard %d.%d", req.VolumeId, req.ShardId) } bufSize := req.Size if bufSize > BufferSizeLimit { bufSize = BufferSizeLimit } buffer := make([]byte, bufSize) startOffset, bytesToRead := req.Offset, req.Size for bytesToRead > 0 { bytesread, err := ecShard.ReadAt(buffer, startOffset) // println(fileName, "read", bytesread, "bytes, with target", bytesToRead) if bytesread > 0 { if int64(bytesread) > bytesToRead { bytesread = int(bytesToRead) } err = stream.Send(&volume_server_pb.VolumeEcShardReadResponse{ Data: buffer[:bytesread], }) if err != nil { // println("sending", bytesread, "bytes err", err.Error()) return err } bytesToRead -= int64(bytesread) } if err != nil { if err != io.EOF { return err } return nil } } return nil }