options.go

package iavl

import "sync/atomic"

// Statisc about db runtime state
type Statistics struct {
	// Each time GetNode operation hit cache
	cacheHitCnt uint64

	// Each time GetNode and GetFastNode operation miss cache
	cacheMissCnt uint64

	// Each time GetFastNode operation hit cache
	fastCacheHitCnt uint64

	// Each time GetFastNode operation miss cache
	fastCacheMissCnt uint64
}

func (stat *Statistics) IncCacheHitCnt() {
	if stat == nil {
		return
	}
	atomic.AddUint64(&stat.cacheHitCnt, 1)
}

func (stat *Statistics) IncCacheMissCnt() {
	if stat == nil {
		return
	}
	atomic.AddUint64(&stat.cacheMissCnt, 1)
}

func (stat *Statistics) IncFastCacheHitCnt() {
	if stat == nil {
		return
	}
	atomic.AddUint64(&stat.fastCacheHitCnt, 1)
}

func (stat *Statistics) IncFastCacheMissCnt() {
	if stat == nil {
		return
	}
	atomic.AddUint64(&stat.fastCacheMissCnt, 1)
}

func (stat *Statistics) GetCacheHitCnt() uint64 {
	return atomic.LoadUint64(&stat.cacheHitCnt)
}

func (stat *Statistics) GetCacheMissCnt() uint64 {
	return atomic.LoadUint64(&stat.cacheMissCnt)
}

func (stat *Statistics) GetFastCacheHitCnt() uint64 {
	return atomic.LoadUint64(&stat.fastCacheHitCnt)
}

func (stat *Statistics) GetFastCacheMissCnt() uint64 {
	return atomic.LoadUint64(&stat.fastCacheMissCnt)
}

func (stat *Statistics) Reset() {
	atomic.StoreUint64(&stat.cacheHitCnt, 0)
	atomic.StoreUint64(&stat.cacheMissCnt, 0)
	atomic.StoreUint64(&stat.fastCacheHitCnt, 0)
	atomic.StoreUint64(&stat.fastCacheMissCnt, 0)
}

// Options define tree options.
type Options struct {
	// Sync synchronously flushes all writes to storage, using e.g. the fsync syscall.
	// Disabling this significantly improves performance, but can lose data on e.g. power loss.
	Sync bool

	// InitialVersion specifies the initial version number. If any versions already exist below
	// this, an error is returned when loading the tree. Only used for the initial SaveVersion()
	// call.
	InitialVersion uint64

	// When Stat is not nil, statistical logic needs to be executed
	Stat *Statistics

	// Ethereum has found that commit of 100KB is optimal, ref ethereum/go-ethereum#15115
	FlushThreshold int
}

// DefaultOptions returns the default options for IAVL.
func DefaultOptions() Options {
	return Options{FlushThreshold: 100000}
}

// SyncOption sets the Sync option.
func SyncOption(sync bool) Option {
	return func(opts *Options) {
		opts.Sync = sync
	}
}

// InitialVersionOption sets the initial version for the tree.
func InitialVersionOption(iv uint64) Option {
	return func(opts *Options) {
		opts.InitialVersion = iv
	}
}

// StatOption sets the Statistics for the tree.
func StatOption(stats *Statistics) Option {
	return func(opts *Options) {
		opts.Stat = stats
	}
}

// FlushThresholdOption sets the FlushThreshold for the batcher.
func FlushThresholdOption(ft int) Option {
	return func(opts *Options) {
		opts.FlushThreshold = ft
	}
}