[#9999] tree: Add ApplyBatch method

Concurrent Apply can lead to child node applies before parent, so
undo/redo operations will perform. This leads to performance degradation
in case of tree with many sublevels.

Signed-off-by: Dmitrii Stepanov <d.stepanov@yadro.com>

pkg/local_object_storage/engine/tree.go

@@ -110,6 +110,34 @@ func (e *StorageEngine) TreeApply(ctx context.Context, cnr cidSDK.ID, treeID str
 	return nil
 }
 
+// TreeApply implements the pilorama.Forest interface.
+func (e *StorageEngine) TreeApplyBatch(ctx context.Context, cnr cidSDK.ID, treeID string, m []*pilorama.Move) error {
+	ctx, span := tracing.StartSpanFromContext(ctx, "StorageEngine.TreeApplyBatch",
+		trace.WithAttributes(
+			attribute.String("container_id", cnr.EncodeToString()),
+			attribute.String("tree_id", treeID),
+		),
+	)
+	defer span.End()
+
+	index, lst, err := e.getTreeShard(ctx, cnr, treeID)
+	if err != nil && !errors.Is(err, pilorama.ErrTreeNotFound) {
+		return err
+	}
+
+	err = lst[index].TreeApplyBatch(ctx, cnr, treeID, m)
+	if err != nil {
+		if !errors.Is(err, shard.ErrReadOnlyMode) && err != shard.ErrPiloramaDisabled {
+			e.reportShardError(lst[index], "can't perform `TreeApplyBatch`", err,
+				zap.Stringer("cid", cnr),
+				zap.String("tree", treeID),
+				zap.String("trace_id", tracingPkg.GetTraceID(ctx)))
+		}
+		return err
+	}
+	return nil
+}
+
 // TreeGetByPath implements the pilorama.Forest interface.
 func (e *StorageEngine) TreeGetByPath(ctx context.Context, cid cidSDK.ID, treeID string, attr string, path []string, latest bool) ([]pilorama.Node, error) {
 	ctx, span := tracing.StartSpanFromContext(ctx, "StorageEngine.TreeGetByPath",

pkg/local_object_storage/pilorama/batch.go

@@ -2,8 +2,10 @@ package pilorama
 
 import (
 	"encoding/binary"
+	"fmt"
 	"slices"
 	"sort"
+	"strconv"
 	"sync"
 	"time"
 
@@ -71,12 +73,14 @@ func (b *batch) run() {
 			_, _, _, inTree := b.forest.getState(bTree, stateKey(cKey[:], b.operations[i].Child))
 			if inTree {
 				slow = true
+				fmt.Println("node in tree, slow = true")
 				break
 			}
 
 			key := childrenKey(cKey[:], b.operations[i].Child, 0)
 			k, _ := bTree.Cursor().Seek(key)
 			if len(k) == childrenKeySize && binary.LittleEndian.Uint64(k[1:]) == b.operations[i].Child {
+				fmt.Println("node is parent, slow = true")
 				slow = true
 				break
 			}
@@ -94,6 +98,7 @@ func (b *batch) run() {
 			p := b.operations[i].Parent
 			_, ts, _, inTree := b.forest.getState(bTree, stateKey(cKey[:], p))
 			if !inTree || b.operations[0].Time < ts {
+				fmt.Printf("parent in tree: %s, b.operations[0].Time: %d, ts: %d\n", strconv.FormatBool(inTree), b.operations[0].Time, ts)
 				slow = true
 				break
 			}

pkg/local_object_storage/pilorama/boltdb.go

@@ -559,6 +559,71 @@ func (t *boltForest) TreeApply(ctx context.Context, cnr cidSDK.ID, treeID string
 	return metaerr.Wrap(err)
 }
 
+func (t *boltForest) TreeApplyBatch(ctx context.Context, cnr cidSDK.ID, treeID string, m []*Move) error {
+	var (
+		startedAt = time.Now()
+		success   = false
+	)
+	defer func() {
+		t.metrics.AddMethodDuration("TreeApplyBatch", time.Since(startedAt), success)
+	}()
+
+	_, span := tracing.StartSpanFromContext(ctx, "boltForest.TreeApplyBatch",
+		trace.WithAttributes(
+			attribute.String("container_id", cnr.EncodeToString()),
+			attribute.String("tree_id", treeID),
+		),
+	)
+	defer span.End()
+
+	if len(m) == 0 {
+		return nil
+	}
+
+	t.modeMtx.RLock()
+	defer t.modeMtx.RUnlock()
+
+	if t.mode.NoMetabase() {
+		return ErrDegradedMode
+	} else if t.mode.ReadOnly() {
+		return ErrReadOnlyMode
+	}
+
+	var seen bool
+	fullID := bucketName(cnr, treeID)
+	err := t.db.View(func(tx *bbolt.Tx) error {
+		treeRoot := tx.Bucket(fullID)
+		if treeRoot == nil {
+			success = true
+			return nil
+		}
+
+		b := treeRoot.Bucket(logBucket)
+
+		var logKey [8]byte
+		binary.BigEndian.PutUint64(logKey[:], m[len(m)-1].Time) // it is assumed that the slice is sorted
+		seen = b.Get(logKey[:]) != nil
+		success = true
+		return nil
+	})
+	if err != nil || seen {
+		success = err == nil
+		return metaerr.Wrap(err)
+	}
+
+	err = metaerr.Wrap(t.db.Update(func(tx *bbolt.Tx) error {
+		bLog, bTree, err := t.getTreeBuckets(tx, fullID)
+		if err != nil {
+			return err
+		}
+
+		var lm Move
+		return t.applyOperation(bLog, bTree, m, &lm)
+	}))
+	success = err == nil
+	return metaerr.Wrap(err)
+}
+
 // TreeApplyStream should be used with caution: this method locks other write transactions while `source` is not closed.
 func (t *boltForest) TreeApplyStream(ctx context.Context, cnr cidSDK.ID, treeID string, source <-chan *Move) error {
 	var (
@@ -692,6 +757,7 @@ func (t *boltForest) applyOperation(logBucket, treeBucket *bbolt.Bucket, ms []*M
 	// 1. Undo up until the desired timestamp is here.
 	for len(key) == 8 && ms[0].Time < binary.BigEndian.Uint64(key) {
 		b.Reset(value)
+		fmt.Printf("applyOperation: time %d\n", binary.BigEndian.Uint64(key))
 
 		tmp.Child = r.ReadU64LE()
 		tmp.Parent = r.ReadU64LE()

pkg/local_object_storage/pilorama/forest.go

@@ -112,6 +112,15 @@ func (f *memoryForest) TreeApply(_ context.Context, cnr cid.ID, treeID string, o
 	return s.Apply(op)
 }
 
+func (f *memoryForest) TreeApplyBatch(ctx context.Context, cnr cid.ID, treeID string, ops []*Move) error {
+	for _, op := range ops {
+		if err := f.TreeApply(ctx, cnr, treeID, op, true); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
 func (f *memoryForest) Init() error {
 	return nil
 }

pkg/local_object_storage/pilorama/interface.go

@@ -21,6 +21,8 @@ type Forest interface {
 	// TreeApply applies replicated operation from another node.
 	// If background is true, TreeApply will first check whether an operation exists.
 	TreeApply(ctx context.Context, cnr cidSDK.ID, treeID string, m *Move, backgroundSync bool) error
+	// TreeApplyBatch applies replicated operations from another node.
+	TreeApplyBatch(ctx context.Context, cnr cidSDK.ID, treeID string, m []*Move) error
 	// TreeGetByPath returns all nodes corresponding to the path.
 	// The path is constructed by descending from the root using the values of the
 	// AttributeFilename in meta.

pkg/local_object_storage/shard/tree.go

@@ -106,6 +106,33 @@ func (s *Shard) TreeApply(ctx context.Context, cnr cidSDK.ID, treeID string, m *
 	return s.pilorama.TreeApply(ctx, cnr, treeID, m, backgroundSync)
 }
 
+// TreeApply implements the pilorama.Forest interface.
+func (s *Shard) TreeApplyBatch(ctx context.Context, cnr cidSDK.ID, treeID string, m []*pilorama.Move) error {
+	ctx, span := tracing.StartSpanFromContext(ctx, "Shard.TreeApplyBatch",
+		trace.WithAttributes(
+			attribute.String("shard_id", s.ID().String()),
+			attribute.String("container_id", cnr.EncodeToString()),
+			attribute.String("tree_id", treeID),
+		),
+	)
+	defer span.End()
+
+	if s.pilorama == nil {
+		return ErrPiloramaDisabled
+	}
+
+	s.m.RLock()
+	defer s.m.RUnlock()
+
+	if s.info.Mode.ReadOnly() {
+		return ErrReadOnlyMode
+	}
+	if s.info.Mode.NoMetabase() {
+		return ErrDegradedMode
+	}
+	return s.pilorama.TreeApplyBatch(ctx, cnr, treeID, m)
+}
+
 // TreeGetByPath implements the pilorama.Forest interface.
 func (s *Shard) TreeGetByPath(ctx context.Context, cid cidSDK.ID, treeID string, attr string, path []string, latest bool) ([]pilorama.Node, error) {
 	ctx, span := tracing.StartSpanFromContext(ctx, "Shard.TreeGetByPath",

pkg/services/tree/sync.go

@@ -177,37 +177,29 @@ func mergeOperationStreams(streams []chan *pilorama.Move, merged chan<- *piloram
 func (s *Service) applyOperationStream(ctx context.Context, cid cid.ID, treeID string,
 	operationStream <-chan *pilorama.Move,
 ) uint64 {
-	errGroup, _ := errgroup.WithContext(ctx)
-	const workersCount = 1024
-	errGroup.SetLimit(workersCount)
-
-	// We run TreeApply concurrently for the operation batch. Let's consider two operations
-	// in the batch m1 and m2 such that m1.Time < m2.Time. The engine may apply m2 and fail
-	// on m1. That means the service must start sync from m1.Time in the next iteration and
-	// this height is stored in unappliedOperationHeight.
-	var unappliedOperationHeight uint64 = math.MaxUint64
-	var heightMtx sync.Mutex
-
 	var prev *pilorama.Move
+	var batch []*pilorama.Move
 	for m := range operationStream {
 		// skip already applied op
 		if prev != nil && prev.Time == m.Time {
 			continue
 		}
 		prev = m
+		batch = append(batch, m)
 
-		errGroup.Go(func() error {
+		if len(batch) == 1000 {
-			if err := s.forest.TreeApply(ctx, cid, treeID, m, true); err != nil {
+			if err := s.forest.TreeApplyBatch(ctx, cid, treeID, batch); err != nil {
-				heightMtx.Lock()
+				return batch[0].Time
-				unappliedOperationHeight = min(unappliedOperationHeight, m.Time)
-				heightMtx.Unlock()
-				return err
 			}
-			return nil
+			batch = batch[:0]
-		})
+		}
 	}
-	_ = errGroup.Wait()
+	if len(batch) > 0 {
-	return unappliedOperationHeight
+		if err := s.forest.TreeApplyBatch(ctx, cid, treeID, batch); err != nil {
+			return batch[0].Time
+		}
+	}
+	return math.MaxUint64
 }
 
 func (s *Service) startStream(ctx context.Context, cid cid.ID, treeID string,