forked from TrueCloudLab/restic
Replace FilesInParallel with an errgroup.Group
This commit is contained in:
Alexander Neumann
parent
75906edef5
commit
e046428c94
5 changed files with 227 additions and 300 deletions
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@ -74,65 +74,83 @@ func (err ErrOldIndexFormat) Error() string {
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// LoadIndex loads all index files.
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func (c *Checker) LoadIndex(ctx context.Context) (hints []error, errs []error) {
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debug.Log("Start")
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type indexRes struct {
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Index *repository.Index
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err error
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ID string
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// track spawned goroutines using wg, create a new context which is
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// cancelled as soon as an error occurs.
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wg, ctx := errgroup.WithContext(ctx)
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type FileInfo struct {
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restic.ID
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Size int64
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}
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indexCh := make(chan indexRes)
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type Result struct {
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*repository.Index
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restic.ID
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Err error
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}
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worker := func(ctx context.Context, id restic.ID) error {
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debug.Log("worker got index %v", id)
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idx, err := repository.LoadIndexWithDecoder(ctx, c.repo, id, repository.DecodeIndex)
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ch := make(chan FileInfo)
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resultCh := make(chan Result)
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// send list of index files through ch, which is closed afterwards
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wg.Go(func() error {
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defer close(ch)
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return c.repo.List(ctx, restic.IndexFile, func(id restic.ID, size int64) error {
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select {
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case <-ctx.Done():
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return nil
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case ch <- FileInfo{id, size}:
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}
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return nil
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})
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})
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// a worker receives an index ID from ch, loads the index, and sends it to indexCh
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worker := func() error {
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for fi := range ch {
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debug.Log("worker got file %v", fi.ID.Str())
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idx, err := repository.LoadIndexWithDecoder(ctx, c.repo, fi.ID, repository.DecodeIndex)
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if errors.Cause(err) == repository.ErrOldIndexFormat {
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debug.Log("index %v has old format", id)
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hints = append(hints, ErrOldIndexFormat{id})
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debug.Log("index %v has old format", fi.ID.Str())
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hints = append(hints, ErrOldIndexFormat{fi.ID})
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idx, err = repository.LoadIndexWithDecoder(ctx, c.repo, id, repository.DecodeOldIndex)
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idx, err = repository.LoadIndexWithDecoder(ctx, c.repo, fi.ID, repository.DecodeOldIndex)
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}
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err = errors.Wrapf(err, "error loading index %v", id.Str())
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err = errors.Wrapf(err, "error loading index %v", fi.ID.Str())
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select {
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case indexCh <- indexRes{Index: idx, ID: id.String(), err: err}:
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case resultCh <- Result{idx, fi.ID, err}:
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case <-ctx.Done():
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}
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}
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return nil
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}
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go func() {
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defer close(indexCh)
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debug.Log("start loading indexes in parallel")
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err := repository.FilesInParallel(ctx, c.repo.Backend(), restic.IndexFile, defaultParallelism,
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repository.ParallelWorkFuncParseID(worker))
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debug.Log("loading indexes finished, error: %v", err)
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if err != nil {
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panic(err)
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// final closes indexCh after all workers have terminated
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final := func() error {
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close(resultCh)
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return nil
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}
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}()
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done := make(chan struct{})
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defer close(done)
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// run workers on ch
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wg.Go(func() error {
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return repository.RunWorkers(ctx, defaultParallelism, worker, final)
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})
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// receive decoded indexes
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packToIndex := make(map[restic.ID]restic.IDSet)
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wg.Go(func() error {
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for res := range resultCh {
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debug.Log("process index %v, err %v", res.ID, res.Err)
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for res := range indexCh {
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debug.Log("process index %v, err %v", res.ID, res.err)
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if res.err != nil {
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errs = append(errs, res.err)
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if res.Err != nil {
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errs = append(errs, res.Err)
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continue
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}
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idxID, err := restic.ParseID(res.ID)
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if err != nil {
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errs = append(errs, errors.Errorf("unable to parse as index ID: %v", res.ID))
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continue
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}
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c.indexes[idxID] = res.Index
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c.indexes[res.ID] = res.Index
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c.masterIndex.Insert(res.Index)
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debug.Log("process blobs")
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@ -146,11 +164,18 @@ func (c *Checker) LoadIndex(ctx context.Context) (hints []error, errs []error) {
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if _, ok := packToIndex[blob.PackID]; !ok {
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packToIndex[blob.PackID] = restic.NewIDSet()
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}
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packToIndex[blob.PackID].Insert(idxID)
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packToIndex[blob.PackID].Insert(res.ID)
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}
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debug.Log("%d blobs processed", cnt)
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}
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return nil
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})
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err := wg.Wait()
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if err != nil {
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errs = append(errs, err)
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}
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debug.Log("checking for duplicate packs")
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for packID := range c.packs {
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@ -163,7 +188,7 @@ func (c *Checker) LoadIndex(ctx context.Context) (hints []error, errs []error) {
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}
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}
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err := c.repo.SetIndex(c.masterIndex)
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err = c.repo.SetIndex(c.masterIndex)
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if err != nil {
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debug.Log("SetIndex returned error: %v", err)
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errs = append(errs, err)
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@ -281,12 +306,29 @@ func loadSnapshotTreeIDs(ctx context.Context, repo restic.Repository) (restic.ID
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sync.Mutex
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}
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snapshotWorker := func(ctx context.Context, strID string) error {
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id, err := restic.ParseID(strID)
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if err != nil {
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return err
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}
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// track spawned goroutines using wg, create a new context which is
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// cancelled as soon as an error occurs.
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wg, ctx := errgroup.WithContext(ctx)
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ch := make(chan restic.ID)
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// send list of index files through ch, which is closed afterwards
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wg.Go(func() error {
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defer close(ch)
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return repo.List(ctx, restic.SnapshotFile, func(id restic.ID, size int64) error {
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select {
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case <-ctx.Done():
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return nil
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case ch <- id:
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}
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return nil
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})
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})
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// a worker receives an index ID from ch, loads the snapshot and the tree,
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// and adds the result to errs and trees.
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worker := func() error {
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for id := range ch {
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debug.Log("load snapshot %v", id)
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treeID, err := loadTreeFromSnapshot(ctx, repo, id)
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@ -294,18 +336,22 @@ func loadSnapshotTreeIDs(ctx context.Context, repo restic.Repository) (restic.ID
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errs.Lock()
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errs.errs = append(errs.errs, err)
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errs.Unlock()
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return nil
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continue
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}
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debug.Log("snapshot %v has tree %v", id, treeID)
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trees.Lock()
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trees.IDs = append(trees.IDs, treeID)
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trees.Unlock()
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}
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return nil
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}
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err := repository.FilesInParallel(ctx, repo.Backend(), restic.SnapshotFile, defaultParallelism, snapshotWorker)
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for i := 0; i < defaultParallelism; i++ {
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wg.Go(worker)
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}
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err := wg.Wait()
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if err != nil {
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errs.errs = append(errs.errs, err)
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}
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@ -1,65 +0,0 @@
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package repository
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import (
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"context"
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"github.com/restic/restic/internal/debug"
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"github.com/restic/restic/internal/restic"
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"golang.org/x/sync/errgroup"
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)
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// ParallelWorkFunc gets one file ID to work on. If an error is returned,
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// processing stops. When the contect is cancelled the function should return.
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type ParallelWorkFunc func(ctx context.Context, id string) error
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// ParallelIDWorkFunc gets one restic.ID to work on. If an error is returned,
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// processing stops. When the context is cancelled the function should return.
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type ParallelIDWorkFunc func(ctx context.Context, id restic.ID) error
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// FilesInParallel runs n workers of f in parallel, on the IDs that
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// repo.List(t) yields. If f returns an error, the process is aborted and the
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// first error is returned.
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func FilesInParallel(ctx context.Context, repo restic.Lister, t restic.FileType, n int, f ParallelWorkFunc) error {
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g, ctx := errgroup.WithContext(ctx)
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ch := make(chan string, n)
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g.Go(func() error {
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defer close(ch)
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return repo.List(ctx, t, func(fi restic.FileInfo) error {
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select {
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case <-ctx.Done():
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case ch <- fi.Name:
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}
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return nil
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})
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})
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for i := 0; i < n; i++ {
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g.Go(func() error {
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for name := range ch {
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err := f(ctx, name)
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if err != nil {
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return err
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}
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}
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return nil
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})
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}
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return g.Wait()
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}
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// ParallelWorkFuncParseID converts a function that takes a restic.ID to a
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// function that takes a string. Filenames that do not parse as a restic.ID
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// are ignored.
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func ParallelWorkFuncParseID(f ParallelIDWorkFunc) ParallelWorkFunc {
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return func(ctx context.Context, s string) error {
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id, err := restic.ParseID(s)
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if err != nil {
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debug.Log("invalid ID %q: %v", id, err)
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return nil
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}
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return f(ctx, id)
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}
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}
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@ -1,129 +0,0 @@
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package repository_test
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import (
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"context"
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"math/rand"
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"testing"
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"time"
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"github.com/restic/restic/internal/errors"
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"github.com/restic/restic/internal/restic"
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"github.com/restic/restic/internal/repository"
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rtest "github.com/restic/restic/internal/test"
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)
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type testIDs []string
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var lister = testIDs{
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"40bb581cd36de952985c97a3ff6b21df41ee897d4db2040354caa36a17ff5268",
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"2e15811a4d14ffac66d36a9ff456019d8de4c10c949d45b643f8477d17e92ff3",
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"70c11b3ed521ad6b76d905c002ca98b361fca06aca060a063432c7311155a4da",
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"8056a33e75dccdda701b6c989c7ed0cb71bbb6da13c6427fe5986f0896cc91c0",
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"79d8776200596aa0237b10d470f7b850b86f8a1a80988ef5c8bee2874ce992e2",
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"f9f1f29791c6b79b90b35efd083f17a3b163bbbafb1a2fdf43d46d56cffda289",
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"3834178d05d0f6dd07f872ee0262ff1ace0f0f375768227d3c902b0b66591369",
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"66d5cc68c9186414806f366ae5493ce7f229212993750a4992be4030f6af28c5",
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"ebca5af4f397944f68cd215e3dfa2b197a7ba0f7c17d65d9f7390d0a15cde296",
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"d4511ce6ff732d106275a57e40745c599e987c0da44c42cddbef592aac102437",
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"f366202f0bfeefaedd7b49e2f21a90d3cbddb97d257a74d788dd34e19a684dae",
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"a5c17728ab2433cd50636dd5c6c7068c7a44f2999d09c46e8f528466da8a059d",
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"bae0f9492b9b208233029b87692a1a55cbd7fbe1cf3f6d7bc693ac266a6d6f0e",
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"9d500187913c7510d71d1902703d312c7aaa56f1e98351385b9535fdabae595e",
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"ffbddd8a4c1e54d258bb3e16d3929b546b61af63cb560b3e3061a8bef5b24552",
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"201bb3abf655e7ef71e79ed4fb1079b0502b5acb4d9fad5e72a0de690c50a386",
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"08eb57bbd559758ea96e99f9b7688c30e7b3bcf0c4562ff4535e2d8edeffaeed",
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"e50b7223b04985ff38d9e11d1cba333896ef4264f82bd5d0653a028bce70e542",
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"65a9421cd59cc7b7a71dcd9076136621af607fb4701d2e5c2af23b6396cf2f37",
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"995a655b3521c19b4d0c266222266d89c8fc62889597d61f45f336091e646d57",
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"51ec6f0bce77ed97df2dd7ae849338c3a8155a057da927eedd66e3d61be769ad",
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"7b3923a0c0666431efecdbf6cb171295ec1710b6595eebcba3b576b49d13e214",
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"2cedcc3d14698bea7e4b0546f7d5d48951dd90add59e6f2d44b693fd8913717d",
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"fd6770cbd54858fdbd3d7b4239b985e5599180064d93ca873f27e86e8407d011",
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"9edc51d8e6e04d05c9757848c1bfbfdc8e86b6330982294632488922e59fdb1b",
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"1a6c4fbb24ad724c968b2020417c3d057e6c89e49bdfb11d91006def65eab6a0",
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"cb3b29808cd0adfa2dca1f3a04f98114fbccf4eb487cdd4022f49bd70eeb049b",
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"f55edcb40c619e29a20e432f8aaddc83a649be2c2d1941ccdc474cd2af03d490",
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"e8ccc1763a92de23566b95c3ad1414a098016ece69a885fc8a72782a7517d17c",
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"0fe2e3db8c5a12ad7101a63a0fffee901be54319cfe146bead7aec851722f82d",
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"36be45a6ae7c95ad97cee1b33023be324bce7a7b4b7036e24125679dd9ff5b44",
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"1685ed1a57c37859fbef1f7efb7509f20b84ec17a765605de43104d2fa37884b",
|
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"9d83629a6a004c505b100a0b5d0b246833b63aa067aa9b59e3abd6b74bc4d3a8",
|
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"be49a66b60175c5e2ee273b42165f86ef11bb6518c1c79950bcd3f4c196c98bd",
|
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"0fd89885d821761b4a890782908e75793028747d15ace3c6cbf0ad56582b4fa5",
|
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"94a767519a4e352a88796604943841fea21429f3358b4d5d55596dbda7d15dce",
|
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"8dd07994afe6e572ddc9698fb0d13a0d4c26a38b7992818a71a99d1e0ac2b034",
|
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"f7380a6f795ed31fbeb2945c72c5fd1d45044e5ab152311e75e007fa530f5847",
|
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"5ca1ce01458e484393d7e9c8af42b0ff37a73a2fee0f18e14cff0fb180e33014",
|
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"8f44178be3fe0a2bd41f922576fb7a9b19d589754504be746f56c759df328fda",
|
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"12d33847c2be711c989f37360dd7aa8537fd14972262a4530634a08fdf32a767",
|
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"31e077f5080f78846a00093caff2b6b839519cc47516142eeba9c41d4072a605",
|
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"14f01db8a0054e70222b76d2555d70114b4bf8a0f02084324af2df226f14a795",
|
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"7f5dbbaf31b4551828e8e76cef408375db9fbcdcdb6b5949f2d1b0c4b8632132",
|
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"42a5d9b9bb7e4a16f23ba916bcf87f38c1aa1f2de2ab79736f725850a8ff6a1b",
|
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"e06f8f901ea708beba8712a11b6e2d0be7c4b018d0254204ef269bcdf5e8c6cc",
|
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"d9ba75785bf45b0c4fd3b2365c968099242483f2f0d0c7c20306dac11fae96e9",
|
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"428debbb280873907cef2ec099efe1566e42a59775d6ec74ded0c4048d5a6515",
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"3b51049d4dae701098e55a69536fa31ad2be1adc17b631a695a40e8a294fe9c0",
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"168f88aa4b105e9811f5f79439cc1a689be4eec77f3361d42f22fe8f7ddc74a9",
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"0baa0ab2249b33d64449a899cb7bd8eae5231f0d4ff70f09830dc1faa2e4abee",
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"0c3896d346b580306a49de29f3a78913a41e14b8461b124628c33a64636241f2",
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"b18313f1651c15e100e7179aa3eb8ffa62c3581159eaf7f83156468d19781e42",
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"996361f7d988e48267ccc7e930fed4637be35fe7562b8601dceb7a32313a14c8",
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"dfb4e6268437d53048d22b811048cd045df15693fc6789affd002a0fc80a6e60",
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"34dd044c228727f2226a0c9c06a3e5ceb5e30e31cb7854f8fa1cde846b395a58",
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}
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func (tests testIDs) List(ctx context.Context, t restic.FileType, fn func(restic.FileInfo) error) error {
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for i := 0; i < 500; i++ {
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for _, id := range tests {
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if ctx.Err() != nil {
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return ctx.Err()
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}
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fi := restic.FileInfo{
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Name: id,
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}
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err := fn(fi)
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if err != nil {
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return err
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}
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}
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}
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return nil
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}
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func TestFilesInParallel(t *testing.T) {
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f := func(ctx context.Context, id string) error {
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time.Sleep(1 * time.Millisecond)
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return nil
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}
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for n := 1; n < 5; n++ {
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||||
err := repository.FilesInParallel(context.TODO(), lister, restic.DataFile, n*100, f)
|
||||
rtest.OK(t, err)
|
||||
}
|
||||
}
|
||||
|
||||
var errTest = errors.New("test error")
|
||||
|
||||
func TestFilesInParallelWithError(t *testing.T) {
|
||||
f := func(ctx context.Context, id string) error {
|
||||
time.Sleep(1 * time.Millisecond)
|
||||
|
||||
if rand.Float32() < 0.01 {
|
||||
return errTest
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
for n := 1; n < 5; n++ {
|
||||
err := repository.FilesInParallel(context.TODO(), lister, restic.DataFile, n*100, f)
|
||||
if err != errTest {
|
||||
t.Fatalf("wrong error returned, want %q, got %v", errTest, err)
|
||||
}
|
||||
}
|
||||
}
|
||||
|
|
@ -18,6 +18,7 @@ import (
|
|||
"github.com/restic/restic/internal/hashing"
|
||||
"github.com/restic/restic/internal/pack"
|
||||
"github.com/restic/restic/internal/restic"
|
||||
"golang.org/x/sync/errgroup"
|
||||
)
|
||||
|
||||
// Repository is used to access a repository in a backend.
|
||||
|
|
@ -391,45 +392,84 @@ const loadIndexParallelism = 4
|
|||
func (r *Repository) LoadIndex(ctx context.Context) error {
|
||||
debug.Log("Loading index")
|
||||
|
||||
errCh := make(chan error, 1)
|
||||
indexes := make(chan *Index)
|
||||
// track spawned goroutines using wg, create a new context which is
|
||||
// cancelled as soon as an error occurs.
|
||||
wg, ctx := errgroup.WithContext(ctx)
|
||||
|
||||
worker := func(ctx context.Context, id restic.ID) error {
|
||||
idx, err := LoadIndex(ctx, r, id)
|
||||
type FileInfo struct {
|
||||
restic.ID
|
||||
Size int64
|
||||
}
|
||||
ch := make(chan FileInfo)
|
||||
indexCh := make(chan *Index)
|
||||
|
||||
// send list of index files through ch, which is closed afterwards
|
||||
wg.Go(func() error {
|
||||
defer close(ch)
|
||||
return r.List(ctx, restic.IndexFile, func(id restic.ID, size int64) error {
|
||||
select {
|
||||
case <-ctx.Done():
|
||||
return nil
|
||||
case ch <- FileInfo{id, size}:
|
||||
}
|
||||
return nil
|
||||
})
|
||||
})
|
||||
|
||||
// a worker receives an index ID from ch, loads the index, and sends it to indexCh
|
||||
worker := func() error {
|
||||
for fi := range ch {
|
||||
idx, err := LoadIndex(ctx, r, fi.ID)
|
||||
if err != nil {
|
||||
fmt.Fprintf(os.Stderr, "%v, ignoring\n", err)
|
||||
return nil
|
||||
}
|
||||
|
||||
select {
|
||||
case indexes <- idx:
|
||||
case indexCh <- idx:
|
||||
case <-ctx.Done():
|
||||
}
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
go func() {
|
||||
defer close(indexes)
|
||||
errCh <- FilesInParallel(ctx, r.be, restic.IndexFile, loadIndexParallelism,
|
||||
ParallelWorkFuncParseID(worker))
|
||||
}()
|
||||
// final closes indexCh after all workers have terminated
|
||||
final := func() error {
|
||||
close(indexCh)
|
||||
return nil
|
||||
}
|
||||
|
||||
// run workers on ch
|
||||
wg.Go(func() error {
|
||||
return RunWorkers(ctx, loadIndexParallelism, worker, final)
|
||||
})
|
||||
|
||||
// receive decoded indexes
|
||||
validIndex := restic.NewIDSet()
|
||||
for idx := range indexes {
|
||||
wg.Go(func() error {
|
||||
for idx := range indexCh {
|
||||
id, err := idx.ID()
|
||||
if err == nil {
|
||||
validIndex.Insert(id)
|
||||
}
|
||||
r.idx.Insert(idx)
|
||||
}
|
||||
return nil
|
||||
})
|
||||
|
||||
err := r.PrepareCache(validIndex)
|
||||
err := wg.Wait()
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
return <-errCh
|
||||
// remove index files from the cache which have been removed in the repo
|
||||
err = r.PrepareCache(validIndex)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
// PrepareCache initializes the local cache. indexIDs is the list of IDs of
|
||||
|
|
|
|||
35
internal/repository/worker_group.go
Normal file
35
internal/repository/worker_group.go
Normal file
|
|
@ -0,0 +1,35 @@
|
|||
package repository
|
||||
|
||||
import (
|
||||
"context"
|
||||
|
||||
"golang.org/x/sync/errgroup"
|
||||
)
|
||||
|
||||
// RunWorkers runs count instances of workerFunc using an errgroup.Group.
|
||||
// After all workers have terminated, finalFunc is run. If an error occurs in
|
||||
// one of the workers, it is returned. FinalFunc is always run, regardless of
|
||||
// any other previous errors.
|
||||
func RunWorkers(ctx context.Context, count int, workerFunc, finalFunc func() error) error {
|
||||
wg, ctx := errgroup.WithContext(ctx)
|
||||
|
||||
// run workers
|
||||
for i := 0; i < count; i++ {
|
||||
wg.Go(workerFunc)
|
||||
}
|
||||
|
||||
// wait for termination
|
||||
err := wg.Wait()
|
||||
|
||||
// make sure finalFunc is run
|
||||
finalErr := finalFunc()
|
||||
|
||||
// if the workers returned an error, return it to the caller (disregarding
|
||||
// any error from finalFunc)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
// if not, return the value finalFunc returned
|
||||
return finalErr
|
||||
}
|
||||
Loading…
Reference in a new issue