perf: implement bitpack encoding for LID and MID blocks

cmd/index_analyzer/main.go

@@ -104,6 +104,7 @@ func analyzeIndex(
 	if err := b.Unpack(readBlock()); err != nil {
 		logger.Fatal("error unpacking block info", zap.Error(err))
 	}
+	ver := b.Info.BinaryDataVer
 
 	docsCount := int(b.Info.DocsTotal)
 
@@ -162,7 +163,7 @@ func analyzeIndex(
 		}
 
 		block := &lids.Block{}
-		if err := block.Unpack(data, &lids.UnpackBuffer{}); err != nil {
+		if err := block.Unpack(data, ver, &lids.UnpackBuffer{}); err != nil {
 			logger.Fatal("error unpacking lids block", zap.Error(err))
 		}
 

config/frac_version.go

@@ -9,6 +9,8 @@ const (
 	BinaryDataV1
 	// BinaryDataV2 - MIDs stored in nanoseconds
 	BinaryDataV2
+	// BinaryDataV3 - delta bitpack encoded MIDs and LIDs
+	BinaryDataV3
 )
 
-const CurrentFracVersion = BinaryDataV2
+const CurrentFracVersion = BinaryDataV3

frac/fraction_test.go

@@ -1833,8 +1833,8 @@ func (s *FractionTestSuite) TestFractionInfo() {
 			"index on disk doesn't match. actual value: %d", info.IndexOnDisk)
 	case *Remote:
 		s.Require().Equal(uint64(0), info.MetaOnDisk, "meta on disk doesn't match. actual value")
-		s.Require().True(info.IndexOnDisk > uint64(1400) && info.IndexOnDisk < uint64(1500),
-			"index on disk doesn't match. actual value: %d", info.MetaOnDisk)
+		s.Require().True(info.IndexOnDisk > uint64(1400) && info.IndexOnDisk < uint64(1550),
+			"index on disk doesn't match. actual value: %d", info.IndexOnDisk)
 	default:
 		s.Require().Fail("unsupported fraction type")
 	}

frac/remote.go

@@ -147,7 +147,7 @@ func (f *Remote) createDataProvider(ctx context.Context) (*sealedDataProvider, e
 		docsReader:       &f.docsReader,
 		blocksOffsets:    f.blocksData.BlocksOffsets,
 		lidsTable:        f.blocksData.LIDsTable,
-		lidsLoader:       lids.NewLoader(&f.indexReader, f.indexCache.LIDs),
+		lidsLoader:       lids.NewLoader(f.info.BinaryDataVer, &f.indexReader, f.indexCache.LIDs),
 		tokenBlockLoader: token.NewBlockLoader(f.BaseFileName, &f.indexReader, f.indexCache.Tokens),
 		tokenTableLoader: token.NewTableLoader(f.BaseFileName, &f.indexReader, f.indexCache.TokenTable),
 

frac/sealed.go

@@ -323,7 +323,7 @@ func (f *Sealed) createDataProvider(ctx context.Context) *sealedDataProvider {
 		docsReader:       &f.docsReader,
 		blocksOffsets:    f.blocksData.BlocksOffsets,
 		lidsTable:        f.blocksData.LIDsTable,
-		lidsLoader:       lids.NewLoader(&f.indexReader, f.indexCache.LIDs),
+		lidsLoader:       lids.NewLoader(f.info.BinaryDataVer, &f.indexReader, f.indexCache.LIDs),
 		tokenBlockLoader: token.NewBlockLoader(f.BaseFileName, &f.indexReader, f.indexCache.Tokens),
 		tokenTableLoader: token.NewTableLoader(f.BaseFileName, &f.indexReader, f.indexCache.TokenTable),
 

frac/sealed/lids/block.go

@@ -1,10 +1,10 @@
 package lids
 
 import (
-	"encoding/binary"
 	"math"
 	"unsafe"
 
+	"github.com/ozontech/seq-db/config"
 	"github.com/ozontech/seq-db/packer"
 )
 
@@ -23,21 +23,16 @@ func (b *Block) getLIDs(i int) []uint32 {
 	return b.LIDs[b.Offsets[i]:b.Offsets[i+1]]
 }
 
-func (b *Block) Pack(dst []byte) []byte {
-	lastLID := int64(0)
-	last := b.getCount() - 1
-	for i := 0; i <= last; i++ {
-		for _, lid := range b.getLIDs(i) {
-			dst = binary.AppendVarint(dst, int64(lid)-lastLID)
-			lastLID = int64(lid)
-		}
-
-		if i < last || b.IsLastLID {
-			// when we add this value to prev we must get -1 (or math.MaxUint32 for uint32)
-			// it is the end-marker; see `Block.Unpack()`
-			dst = binary.AppendVarint(dst, -1-lastLID)
-		}
+func (b *Block) Pack(dst []byte, buf []uint32) []byte {
+	if b.IsLastLID {
+		dst = append(dst, 1)
+	} else {
+		dst = append(dst, 0)
 	}
+
+	dst = packer.CompressDeltaBitpackUint32(dst, b.Offsets, buf)
+	dst = packer.CompressDeltaBitpackUint32(dst, b.LIDs, buf)
+
 	return dst
 }
 
@@ -49,13 +44,46 @@ func (b *Block) GetSizeBytes() int {
 	return blockSize + uint32Size*cap(b.LIDs) + uint32Size*cap(b.Offsets)
 }
 
-func (b *Block) Unpack(data []byte, buf *UnpackBuffer) error {
+func (b *Block) Unpack(data []byte, fracVer config.BinaryDataVersion, buf *UnpackBuffer) error {
+	buf.Reset()
+
+	if fracVer >= config.BinaryDataV3 {
+		return b.unpackBitpack(data, buf)
+	}
+
+	return b.unpackVarint(data, buf)
+}
+
+func (b *Block) unpackBitpack(data []byte, buf *UnpackBuffer) error {
+	if data[0] == 1 {
+		b.IsLastLID = true
+	} else {
+		b.IsLastLID = false
+	}
+	data = data[1:]
+
+	var err error
+	var values []uint32
+
+	data, values, err = packer.DecompressDeltaBitpackUint32(data, buf.decompressed)
+	if err != nil {
+		return err
+	}
+	b.Offsets = append([]uint32{}, values...)
+
+	data, values, err = packer.DecompressDeltaBitpackUint32(data, buf.decompressed)
+	if err != nil {
+		return err
+	}
+	b.LIDs = append([]uint32{}, values...)
+	return nil
+}
+
+func (b *Block) unpackVarint(data []byte, buf *UnpackBuffer) error {
 	var lid, offset uint32
 
 	b.IsLastLID = true
 
-	buf.lids = buf.lids[:0]
-	buf.offsets = buf.offsets[:0]
 	buf.offsets = append(buf.offsets, 0) // first offset is always zero
 
 	unpacker := packer.NewBytesUnpacker(data)