pkg/local_object_storage/pilorama/batch.go

@@ -50,10 +50,23 @@ func (b *batch) run() {
 			return b.operations[i].Time < b.operations[j].Time
 		})
 
+		b.operations = removeDuplicatesInPlace(b.operations)
 		var lm Move
 		return b.forest.applyOperation(bLog, bTree, b.operations, &lm)
 	})
-	for i := range b.operations {
+	for i := range b.results {
 		b.results[i] <- err
 	}
 }
+
+func removeDuplicatesInPlace(a []*Move) []*Move {
+	equalCount := 0
+	for i := 1; i < len(a); i++ {
+		if a[i].Time == a[i-1].Time {
+			equalCount++
+		} else {
+			a[i-equalCount] = a[i]
+		}
+	}
+	return a[:len(a)-equalCount]
+}

pkg/local_object_storage/pilorama/batch_test.go

@@ -0,0 +1,70 @@
+package pilorama
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func Test_removeDuplicatesInPlace(t *testing.T) {
+	testCases := []struct {
+		before []int
+		after  []int
+	}{
+		{
+			before: []int{},
+			after:  []int{},
+		},
+		{
+			before: []int{1},
+			after:  []int{1},
+		},
+		{
+			before: []int{1, 2},
+			after:  []int{1, 2},
+		},
+		{
+			before: []int{1, 2, 3},
+			after:  []int{1, 2, 3},
+		},
+		{
+			before: []int{1, 1, 2},
+			after:  []int{1, 2},
+		},
+		{
+			before: []int{1, 2, 2},
+			after:  []int{1, 2},
+		},
+		{
+			before: []int{1, 2, 2, 3},
+			after:  []int{1, 2, 3},
+		},
+		{
+			before: []int{1, 1, 1},
+			after:  []int{1},
+		},
+		{
+			before: []int{1, 1, 2, 2},
+			after:  []int{1, 2},
+		},
+		{
+			before: []int{1, 1, 1, 2, 3, 3, 3},
+			after:  []int{1, 2, 3},
+		},
+	}
+
+	for _, tc := range testCases {
+		ops := make([]*Move, len(tc.before))
+		for i := range ops {
+			ops[i] = &Move{Meta: Meta{Time: Timestamp(tc.before[i])}}
+		}
+
+		expected := make([]*Move, len(tc.after))
+		for i := range expected {
+			expected[i] = &Move{Meta: Meta{Time: Timestamp(tc.after[i])}}
+		}
+
+		actual := removeDuplicatesInPlace(ops)
+		require.Equal(t, expected, actual, "%d", tc.before)
+	}
+}

pkg/local_object_storage/pilorama/forest_test.go

@@ -1,6 +1,7 @@
 package pilorama
 
 import (
+	"context"
 	"fmt"
 	"math/rand"
 	"os"
@@ -13,6 +14,7 @@ import (
 	cidtest "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/container/id/test"
 	objectSDK "git.frostfs.info/TrueCloudLab/frostfs-sdk-go/object"
 	"github.com/stretchr/testify/require"
+	"golang.org/x/sync/errgroup"
 )
 
 var providers = []struct {
@@ -445,6 +447,82 @@ func testForestTreeApply(t *testing.T, constructor func(t testing.TB, _ ...Optio
 	})
 }
 
+func TestForest_ApplySameOperation(t *testing.T) {
+	for i := range providers {
+		t.Run(providers[i].name, func(t *testing.T) {
+			parallel := providers[i].name != "inmemory"
+			testForestApplySameOperation(t, providers[i].construct, parallel)
+		})
+	}
+}
+
+func testForestApplySameOperation(t *testing.T, constructor func(t testing.TB, _ ...Option) Forest, parallel bool) {
+	cid := cidtest.ID()
+	treeID := "version"
+
+	batchSize := 3
+	errG, _ := errgroup.WithContext(context.Background())
+	if !parallel {
+		batchSize = 1
+		errG.SetLimit(1)
+	}
+
+	meta := []Meta{
+		{Time: 1, Items: []KeyValue{{AttributeFilename, []byte("1")}, {"attr", []byte{1}}}},
+		{Time: 2, Items: []KeyValue{{AttributeFilename, []byte("2")}, {"attr", []byte{1}}}},
+		{Time: 3, Items: []KeyValue{{AttributeFilename, []byte("3")}, {"attr", []byte{1}}}},
+	}
+	logs := []Move{
+		{
+			Child:  1,
+			Parent: RootID,
+			Meta:   meta[0],
+		},
+		{
+			Child:  2,
+			Parent: 1,
+			Meta:   meta[1],
+		},
+		{
+			Child:  1,
+			Parent: 2,
+			Meta:   meta[2],
+		},
+	}
+
+	check := func(t *testing.T, s Forest) {
+		testMeta(t, s, cid, treeID, 1, RootID, meta[0])
+		testMeta(t, s, cid, treeID, 2, 1, meta[1])
+
+		nodes, err := s.TreeGetChildren(cid, treeID, RootID)
+		require.NoError(t, err)
+		require.Equal(t, []Node{1}, nodes)
+
+		nodes, err = s.TreeGetChildren(cid, treeID, 1)
+		require.NoError(t, err)
+		require.Equal(t, []Node{2}, nodes)
+	}
+
+	t.Run("expected", func(t *testing.T) {
+		s := constructor(t)
+		for i := range logs {
+			require.NoError(t, s.TreeApply(cid, treeID, &logs[i], false))
+		}
+		check(t, s)
+	})
+
+	s := constructor(t, WithMaxBatchSize(batchSize))
+	require.NoError(t, s.TreeApply(cid, treeID, &logs[0], false))
+	for i := 0; i < batchSize; i++ {
+		errG.Go(func() error {
+			return s.TreeApply(cid, treeID, &logs[2], false)
+		})
+	}
+	require.NoError(t, errG.Wait())
+	require.NoError(t, s.TreeApply(cid, treeID, &logs[1], false))
+	check(t, s)
+}
+
 func TestForest_GetOpLog(t *testing.T) {
 	for i := range providers {
 		t.Run(providers[i].name, func(t *testing.T) {

pkg/services/tree/sync.go

@@ -206,28 +206,26 @@ func (s *Service) synchronizeSingle(ctx context.Context, cid cid.ID, treeID stri
 	errG, ctx := errgroup.WithContext(ctx)
 	errG.SetLimit(1024)
 
-	var heightMtx sync.Mutex
-
 	for {
-		newHeight := height
 		req := &GetOpLogRequest{
 			Body: &GetOpLogRequest_Body{
 				ContainerId: rawCID,
 				TreeId:      treeID,
-				Height:      newHeight,
+				Height:      height,
 			},
 		}
 		if err := SignMessage(req, s.key); err != nil {
 			_ = errG.Wait()
-			return newHeight, err
+			return height, err
 		}
 
 		c, err := treeClient.GetOpLog(ctx, req)
 		if err != nil {
 			_ = errG.Wait()
-			return newHeight, fmt.Errorf("can't initialize client: %w", err)
+			return height, fmt.Errorf("can't initialize client: %w", err)
 		}
 
+		lastApplied := height
 		res, err := c.Recv()
 		for ; err == nil; res, err = c.Recv() {
 			lm := res.GetBody().GetOperation()
@@ -237,39 +235,27 @@ func (s *Service) synchronizeSingle(ctx context.Context, cid cid.ID, treeID stri
 			}
 			if err := m.Meta.FromBytes(lm.Meta); err != nil {
 				_ = errG.Wait()
-				return newHeight, err
+				return height, err
+			}
+			if lastApplied < m.Meta.Time {
+				lastApplied = m.Meta.Time
 			}
 			errG.Go(func() error {
-				err := s.forest.TreeApply(cid, treeID, m, true)
-				heightMtx.Lock()
-				defer heightMtx.Unlock()
-				if err != nil {
-					if newHeight > height {
-						height = newHeight
-					}
-					return err
-				}
-				if m.Time > newHeight {
-					newHeight = m.Time + 1
-				} else {
-					newHeight++
-				}
-				return nil
+				return s.forest.TreeApply(cid, treeID, m, true)
 			})
 		}
 
+		// First check local errors: if everything is ok, we can update starting height,
+		// because everything was applied.
 		applyErr := errG.Wait()
-		if err == nil {
-			err = applyErr
+		if applyErr != nil {
+			return height, applyErr
 		}
 
-		heightMtx.Lock()
-		if height == newHeight || err != nil && !errors.Is(err, io.EOF) {
-			heightMtx.Unlock()
-			return newHeight, err
+		height = lastApplied
+		if err != nil && !errors.Is(err, io.EOF) {
+			return height, err
 		}
-		height = newHeight
-		heightMtx.Unlock()
 	}
 }