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db

package

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Versions in this module

v0

v0.3.0

Feb 7, 2026

Changes in this version

type DB

+ func (db *DB) Dir() string

+ func (db *DB) RefreshValueLogSet() error

+ func (db *DB) ValueLogGC(ctx context.Context, opts ValueLogGCOptions) (ValueLogGCStats, error)

+ type DurabilityMode uint8

+ const DurabilityDurable

+ const DurabilityWALOffRelaxed

+ const DurabilityWALOnRelaxed

+ type IntegrityMode uint8

+ const IntegritySkipChecksums

+ const IntegrityVerify

type Options

+ DictDBChunkSize int64

+ DisableSideStores bool

+ Durability DurabilityMode

+ FlushBackendMaxBatches int

+ FlushBackendMaxEntries int

+ FlushBuildChunkCap int

+ FlushBuildChunkMaxBytes int

+ FlushBuildChunkMinBytes int

+ FlushBuildChunkTargetBytes int

+ FlushBuildMinEntries int

+ FlushBuildMinUnits int

+ FlushBuildPrefetchUnits int

+ IndexPackedValuePtr bool

+ MaintenanceOpsPerCoalesce int

+ PagerMmapPopulate bool

+ PagerPrefetchOnRead bool

+ PagerSyncConcurrency int

+ TemplateDBChunkSize int64

+ ValueLog ValueLogOptions

+ type ValueLogAutoPolicy uint8

+ const ValueLogAutoBalanced

+ const ValueLogAutoSize

+ const ValueLogAutoThroughput

+ type ValueLogBlockCodec uint8

+ const ValueLogBlockLZ4

+ const ValueLogBlockSnappy

+ type ValueLogCompressionMode uint8

+ const ValueLogCompressionAuto

+ const ValueLogCompressionBlock

+ const ValueLogCompressionDict

+ const ValueLogCompressionOff

+ type ValueLogGCOptions struct

+ DryRun bool

+ type ValueLogGCStats struct

+ BytesActive int64

+ BytesDeleted int64

+ BytesEligible int64

+ BytesReferenced int64

+ BytesTotal int64

+ SegmentsActive int

+ SegmentsDeleted int

+ SegmentsEligible int

+ SegmentsReferenced int

+ SegmentsTotal int

+ type ValueLogOptions struct

+ AutoPolicy ValueLogAutoPolicy

+ BlockCodec ValueLogBlockCodec

+ BlockTargetCompressedBytes int

+ Compression ValueLogCompressionMode

+ CompressionAutotune valuelog.AutotuneOptions

+ DictAdaptiveRatio float64

+ DictFrameEnableEntropy bool

+ DictFrameEncodeLevel zstd.EncoderLevel

+ DictIncompressibleHoldBytes int

+ DictLookup valuelog.DictLookup

+ DictMaxK int

+ DictMetricsMinRecords int

+ DictMetricsPauseBytes int

+ DictMetricsWindowBytes int

+ DictMinPayloadSavingsRatio float64

+ DictProbeIntervalBytes int

+ DictTrain compression.TrainConfig

+ ForcePointers bool

+ IncompressibleHoldBytes int

+ IncompressibleProbeIntervalBytes int

+ MaxRetainedBytes int64

+ MaxRetainedBytesHard int64

+ PointerThreshold int

+ RawWritevMinAvgBytes int

+ RawWritevMinBatchRecords int

+ ReadIntegrity IntegrityMode

+ TemplateConfig template.Config

+ TemplateDecodeOptions template.DecodeOptions

+ TemplateLookup valuelog.TemplateLookup

+ TemplateMode template.Mode

+ TemplateReadStrict bool

+ type ValueLogRewriteStats struct

+ BytesAfter int64

+ BytesBefore int64

+ RecordsCopied int

+ SegmentsAfter int

+ SegmentsBefore int

+ func ValueLogRewriteOffline(opts Options) (ValueLogRewriteStats, error)

v0.2.0

Jan 24, 2026

Changes in this version

type Batch

+ func (b *Batch) SetPointerView(key []byte, ptr page.ValuePtr) error

type Options

+ DictLookup valuelog.DictLookup

+ DisableJournal bool

+ IndexColumnarLeaves bool

+ IndexInternalBaseDelta bool

+ JournalCompression bool

+ JournalLanes int

+ ValueLogCompressionAutotune valuelog.AutotuneOptions

+ ValueLogDictAdaptiveRatio float64

+ ValueLogDictMetricsMinRecords int

+ ValueLogDictMetricsPauseBytes int

+ ValueLogDictMetricsWindowBytes int

+ ValueLogDictMinPayloadSavingsRatio float64

+ ValueLogDictTrain compression.TrainConfig

v0.1.0

Jan 23, 2026

Changes in this version

+ const KeepRecent

+ const MetaPage0ID

+ const MetaPage1ID

+ var ErrLocked = lockfile.ErrLocked

+ var ErrReadOnly = errors.New("treedb: read-only")

+ var ErrUnsafeOptions = errors.New("treedb: unsafe options require AllowUnsafe")

+ var ErrVacuumInProgress = errors.New("online vacuum already in progress")

+ var ErrVacuumUnsupported = errors.New("online vacuum unsupported on this platform")

+ func VacuumIndexOffline(opts Options) error

+ func ValidateFragmentationReport(rep map[string]string) error

+ func ValueReaderForState(state *DBState) tree.SlabReader

+ type Batch struct

+ func (b *Batch) Close() error

+ func (b *Batch) Delete(key []byte) error

+ func (b *Batch) DeleteView(key []byte) error

+ func (b *Batch) GetByteSize() (int, error)

+ func (b *Batch) Replay(fn func(batch.Entry) error) error

+ func (b *Batch) Reset()

+ func (b *Batch) Set(key, value []byte) error

+ func (b *Batch) SetOps(ops []batch.Entry) error

+ func (b *Batch) SetPointer(key []byte, ptr page.ValuePtr) error

+ func (b *Batch) SetView(key, value []byte) error

+ func (b *Batch) Write() error

+ func (b *Batch) WriteSync() error

+ type CompactionOp struct

+ Key []byte

+ NewPtr page.ValuePtr

+ OldPtr page.ValuePtr

+ type DB struct

+ func Open(opts Options) (*DB, error)

+ func (db *DB) AcquireSnapshot() *Snapshot

+ func (db *DB) ApplyCompaction(ops []CompactionOp) error

+ func (db *DB) ApplyCompactionMicroBatches(ops []CompactionOp, maxOps int) error

+ func (db *DB) Close() error

+ func (db *DB) Commit(newRootID uint64) error

+ func (db *DB) CompactIndex() error

+ func (db *DB) CompactSlabsIndexSwap(ctx context.Context, slabIDs []uint32, opts IndexSwapCompactionOptions) error

+ func (db *DB) Delete(key []byte) error

+ func (db *DB) DeleteSync(key []byte) error

+ func (db *DB) FragmentationReport() (map[string]string, error)

+ func (db *DB) Get(key []byte) ([]byte, error)

+ func (db *DB) GetAppend(key, dst []byte) ([]byte, error)

+ func (db *DB) GetUnsafe(key []byte) ([]byte, error)

+ func (db *DB) Has(key []byte) (bool, error)

+ func (db *DB) InlineThreshold() int

+ func (db *DB) Iterator(start, end []byte) (iterator.UnsafeIterator, error)

+ func (db *DB) MarkValueLogZombie(id uint32) error

+ func (db *DB) NewBatch() batch.Interface

+ func (db *DB) NewBatchWithSize(size int) batch.Interface

+ func (db *DB) Pager() *pager.Pager

+ func (db *DB) Print() error

+ func (db *DB) Prune()

+ func (db *DB) RefreshSlabSet() error

+ func (db *DB) ReverseIterator(start, end []byte) (iterator.UnsafeIterator, error)

+ func (db *DB) Set(key, value []byte) error

+ func (db *DB) SetSync(key, value []byte) error

+ func (db *DB) SlabManager() *slab.SlabManager

+ func (db *DB) State() *DBState

+ func (db *DB) Stats() map[string]string

+ func (db *DB) VacuumIndexOnline(ctx context.Context) error

+ func (db *DB) Zipper() *zipper.Zipper

+ type DBIterator struct

+ func (it *DBIterator) Close() error

+ func (it *DBIterator) DebugStats() (queueLen int, sourcesUsed int)

+ func (it *DBIterator) Domain() (start, end []byte)

+ func (it *DBIterator) Error() error

+ func (it *DBIterator) IsDeleted() bool

+ func (it *DBIterator) Key() []byte

+ func (it *DBIterator) KeyCopy(dst []byte) []byte

+ func (it *DBIterator) Next()

+ func (it *DBIterator) Seek(key []byte)

+ func (it *DBIterator) UnsafeEntry() ([]byte, page.ValuePtr, byte)

+ func (it *DBIterator) UnsafeKey() []byte

+ func (it *DBIterator) UnsafeValue() []byte

+ func (it *DBIterator) Valid() bool

+ func (it *DBIterator) Value() []byte

+ func (it *DBIterator) ValueCopy(dst []byte) []byte

+ type DBState struct

+ CommitSeq uint64

+ RootPageID uint64

+ SlabSet *slab.SlabSet

+ SystemRootPageID uint64

+ ValueLogSet *vlog.Set

+ type IndexSwapCompactionOptions struct

+ Assist func()

+ CopyBurstBytes int64

+ CopyBytesPerSec int64

+ Stats *IndexSwapCompactionStats

+ type IndexSwapCompactionStats struct

+ BuildNanos uint64

+ CatchupNanos uint64

+ FinalizeNanos uint64

+ RemapBytes uint64

+ RemapCount uint64

+ SlabDeadBytes int

+ SlabWriteBytes int

+ TotalNanos uint64

+ type Iterator interface

+ Close func() error

+ Error func() error

+ Key func() []byte

+ KeyCopy func(dst []byte) []byte

+ Next func()

+ Reset func(start, end []byte)

+ Valid func() bool

+ Value func() []byte

+ ValueCopy func(dst []byte) []byte

+ type Mode uint8

+ const ModeBackend

+ const ModeCached

+ type Options struct

+ AllowUnsafe bool

+ BackgroundCheckpointIdleDuration time.Duration

+ BackgroundCheckpointInterval time.Duration

+ BackgroundCompactionCopyBurstBytes int64

+ BackgroundCompactionCopyBytesPerSec int64

+ BackgroundCompactionDeadRatio float64

+ BackgroundCompactionIndexSwap bool

+ BackgroundCompactionInterval time.Duration

+ BackgroundCompactionMaxSlabs int

+ BackgroundCompactionMicroBatch int

+ BackgroundCompactionMinBytes uint64

+ BackgroundCompactionRotateBeforeWrite bool

+ BackgroundIndexVacuumInterval time.Duration

+ BackgroundIndexVacuumSpanRatioPPM uint32

+ ChunkSize int64

+ Dir string

+ DisableBackgroundPrune bool

+ DisablePiggybackCompaction bool

+ DisableReadChecksum bool

+ DisableSlabTailRepairOnOpen bool

+ DisableValueLog bool

+ DisableWAL bool

+ FlushBuildConcurrency int

+ FlushThreshold int64

+ ForceValuePointers bool

+ FreelistRegionPages uint64

+ FreelistRegionRadius int

+ InternalFillTargetPPM uint32

+ KeepRecent uint64

+ LeafFillTargetPPM uint32

+ LeafPrefixCompression bool

+ MaxBacklogBytes int64

+ MaxQueuedMemtables int

+ MaxValueLogRetainedBytes int64

+ MaxValueLogRetainedBytesHard int64

+ MaxWALBytes int64

+ MemtableMode string

+ MemtableShards int

+ MemtableValueLogPointers bool

+ Mode Mode

+ NotifyError func(error)

+ PreferAppendAlloc bool

+ PruneInterval time.Duration

+ PruneMaxDuration time.Duration

+ PruneMaxPages int

+ ReadOnly bool

+ RelaxedSync bool

+ SlabCompression slab.CompressionOptions

+ SlowdownBacklogSeconds float64

+ SplitValueLog bool

+ StopBacklogSeconds float64

+ ValueLogPointerThreshold int

+ VerifyOnRead bool

+ WALMaxSegmentBytes int64

+ WriterFlushMaxDuration time.Duration

+ WriterFlushMaxMemtables int

+ type Snapshot struct

+ func (s *Snapshot) Close() error

+ func (s *Snapshot) Get(key []byte) ([]byte, error)

+ func (s *Snapshot) GetEntry(key []byte) (node.LeafEntry, error)

+ func (s *Snapshot) GetUnsafe(key []byte) ([]byte, error)

+ func (s *Snapshot) Has(key []byte) (bool, error)

+ func (s *Snapshot) Pager() *pager.Pager

+ func (s *Snapshot) State() *DBState

+ type SnapshotPool struct

+ func NewSnapshotPool() *SnapshotPool

+ func (p *SnapshotPool) Get() *Snapshot

+ func (p *SnapshotPool) Put(s *Snapshot)

+ type WritePolicy struct

+ FlushThreshold int64

+ InlineThreshold int

+ func DefaultWritePolicy() WritePolicy