Options

About options see here for detail.

Arguments	Comment	Type
Dir	Dir represents Open the database located in which dir.	string
EntryIdxMode	EntryIdxMode represents using which mode to index the entries. EntryIdxMode includes three options: HintKeyValAndRAMIdxMode,HintKeyAndRAMIdxMode and HintBPTSparseIdxMode. HintKeyValAndRAMIdxMode represents ram index (key and value) mode, HintKeyAndRAMIdxMode represents ram index (only key) mode and HintBPTSparseIdxMode represents b+ tree sparse index mode.	EntryIdxMode
RWMode	RWMode represents the read and write mode. RWMode includes two options: FileIO and MMap. FileIO represents the read and write mode using standard I/O. And MMap represents the read and write mode using mmap.	RWMode
SegmentSize	NutsDB will truncate data file if the active file is larger than SegmentSize. Current version default SegmentSize is 8MB,but you can custom it. The defaultSegmentSize becomes 256MB when the version is greater than 0.8.0. Once set, it cannot be changed. see caveats--limitations for detail.	int64
NodeNum	NodeNum represents the node number.Default NodeNum is 1. NodeNum range [1,1023] .	int64
SyncEnable	SyncEnable represents if call Sync() function. if SyncEnable is false, high write performance but potential data loss likely. if SyncEnable is true, slower but persistent.	bool
MaxFdNumsInCache	MaxFdNumsInCache represents the max numbers of fd in cache.	int
CleanFdsCacheThreshold	CleanFdsCacheThreshold represents the maximum threshold for recycling fd (0-1).	float64
BufferSizeOfRecovery	BufferSizeOfRecovery represents the buffer size of recovery reader.	int
GCWhenClose	GCWhenClose represents initiative GC when calling db.Close(). Nutsdb doesn't immediately trigger GC on db.Close() by default.	bool
CommitBufferSize	CommitBufferSize represent the size of memory preallocated for transaction. Nutsdb will preallocate memory and reducing the number of memory allocations.	int64
ErrorHandler	ErrorHandler handles an error that occur during transaction.	ErrorHandler
LessFunc	LessFunc represents func to sort keys. Nutsdb sorts keys in lexicographical order by default.	LessFunc
MergeInterval	MergeInterval represent the interval for automatic merges, with 0 meaning automatic merging is disabled. Default interval is 2 hours.	time.Duration
MaxBatchCount	MaxBatchCount represents max entries in batch.	int64
MaxBatchSize	MaxBatchSize represents max batch size in bytes.	int64
MaxWriteRecordCount	MaxWriteRecordCount represents max write record number.	int64
HintKeyAndRAMIdxCacheSize	Cache size for HintKeyAndRAMIdxMode. When set to 0, caching is disabled.	int
TTLConfig	Configure TTL scanning and batching behavior. BatchSize=100, BatchTimeout=1s, QueueSize=1000 by default. Also includes timing wheel settings: EnableTimingWheel=true, WheelSlotDuration=1s, WheelSize=3600.	struct
EnableHintFile	Enable/disable hint file feature.	bool
EnableMergeV2	Enable/disable Merge V2 algorithm.	bool
ListImpl	Specifies the implementation type for List data structure (default: ListImplBTree).	ListImplementationType
EnableWatch	EnableWatch toggles the watch feature. If EnableWatch is true, the watch feature will be enabled. The watch feature will be disabled by default.	bool

Default Options

Recommend to use the DefaultOptions. Unless you know what you're doing.

var DefaultOptions = func() Options {
    return Options{
        EntryIdxMode:              HintKeyValAndRAMIdxMode,
        SegmentSize:               defaultSegmentSize,
        NodeNum:                   1,
        RWMode:                    FileIO,
        SyncEnable:                true,
        MaxFdNumsInCache:          0,
        CleanFdsCacheThreshold:    0,
        BufferSizeOfRecovery:      0,
        CommitBufferSize:          4 * MB,
        MergeInterval:             2 * time.Hour,
        MaxBatchSize:              (15 * defaultSegmentSize / 4) / 100,
        MaxBatchCount:             (15 * defaultSegmentSize / 4) / 100 / 100,
        MaxWriteRecordCount:       0,
        HintKeyAndRAMIdxCacheSize: 0,
        TTLConfig:                 ttl.DefaultConfig(),
        EnableHintFile:            false,
        EnableMergeV2:             false,
        ListImpl:                  ListImplementationType(ListImplBTree),
        EnableWatch:               false,
    }
}()