支持lru淘汰preparestmt cache

gorm.go

@@ -34,6 +34,8 @@ type Config struct {
 	DryRun bool
 	// PrepareStmt executes the given query in cached statement
 	PrepareStmt bool
+	// PrepareStmt cache support LRU expired
+	PrepareStmtLruConfig *PrepareStmtLruConfig
 	// DisableAutomaticPing
 	DisableAutomaticPing bool
 	// DisableForeignKeyConstraintWhenMigrating
@@ -65,6 +67,11 @@ type Config struct {
 	callbacks  *callbacks
 	cacheStore *sync.Map
 }
+type PrepareStmtLruConfig struct {
+	Size int
+	TTL  time.Duration
+	Open bool
+}
 
 // Apply update config to new config
 func (c *Config) Apply(config *Config) error {
@@ -197,7 +204,7 @@ func Open(dialector Dialector, opts ...Option) (db *DB, err error) {
 	}
 
 	if config.PrepareStmt {
-		preparedStmt := NewPreparedStmtDB(db.ConnPool)
+		preparedStmt := NewPreparedStmtDB(db.ConnPool, config.PrepareStmtLruConfig)
 		db.cacheStore.Store(preparedStmtDBKey, preparedStmt)
 		db.ConnPool = preparedStmt
 	}
@@ -268,7 +275,7 @@ func (db *DB) Session(config *Session) *DB {
 		if v, ok := db.cacheStore.Load(preparedStmtDBKey); ok {
 			preparedStmt = v.(*PreparedStmtDB)
 		} else {
-			preparedStmt = NewPreparedStmtDB(db.ConnPool)
+			preparedStmt = NewPreparedStmtDB(db.ConnPool, db.Config.PrepareStmtLruConfig)
 			db.cacheStore.Store(preparedStmtDBKey, preparedStmt)
 		}
 

lru.go

@@ -0,0 +1,493 @@
+package gorm
+
+// golang -lru
+//https://github.com/hashicorp/golang-lru
+import (
+	"sync"
+	"time"
+)
+
+// EvictCallback is used to get a callback when a cache entry is evicted
+type EvictCallback[K comparable, V any] func(key K, value V)
+
+// LRU implements a thread-safe LRU with expirable entries.
+type LRU[K comparable, V any] struct {
+	size      int
+	evictList *LruList[K, V]
+	items     map[K]*Entry[K, V]
+	onEvict   EvictCallback[K, V]
+
+	// expirable options
+	mu   sync.Mutex
+	ttl  time.Duration
+	done chan struct{}
+
+	// buckets for expiration
+	buckets []bucket[K, V]
+	// uint8 because it's number between 0 and numBuckets
+	nextCleanupBucket uint8
+}
+
+// bucket is a container for holding entries to be expired
+type bucket[K comparable, V any] struct {
+	entries     map[K]*Entry[K, V]
+	newestEntry time.Time
+}
+
+// noEvictionTTL - very long ttl to prevent eviction
+const noEvictionTTL = time.Hour * 24 * 365 * 10
+
+// because of uint8 usage for nextCleanupBucket, should not exceed 256.
+// casting it as uint8 explicitly requires type conversions in multiple places
+const numBuckets = 100
+
+// NewLRU returns a new thread-safe cache with expirable entries.
+//
+// Size parameter set to 0 makes cache of unlimited size, e.g. turns LRU mechanism off.
+//
+// Providing 0 TTL turns expiring off.
+//
+// Delete expired entries every 1/100th of ttl value. Goroutine which deletes expired entries runs indefinitely.
+func NewLRU[K comparable, V any](size int, onEvict EvictCallback[K, V], ttl time.Duration) *LRU[K, V] {
+	if size < 0 {
+		size = 0
+	}
+	if ttl <= 0 {
+		ttl = noEvictionTTL
+	}
+
+	res := LRU[K, V]{
+		ttl:       ttl,
+		size:      size,
+		evictList: NewList[K, V](),
+		items:     make(map[K]*Entry[K, V]),
+		onEvict:   onEvict,
+		done:      make(chan struct{}),
+	}
+
+	// initialize the buckets
+	res.buckets = make([]bucket[K, V], numBuckets)
+	for i := 0; i < numBuckets; i++ {
+		res.buckets[i] = bucket[K, V]{entries: make(map[K]*Entry[K, V])}
+	}
+
+	// enable deleteExpired() running in separate goroutine for cache with non-zero TTL
+	//
+	// Important: done channel is never closed, so deleteExpired() goroutine will never exit,
+	// it's decided to add functionality to close it in the version later than v2.
+	if res.ttl != noEvictionTTL {
+		go func(done <-chan struct{}) {
+			ticker := time.NewTicker(res.ttl / numBuckets)
+			defer ticker.Stop()
+			for {
+				select {
+				case <-done:
+					return
+				case <-ticker.C:
+					res.deleteExpired()
+				}
+			}
+		}(res.done)
+	}
+	return &res
+}
+
+// Purge clears the cache completely.
+// onEvict is called for each evicted key.
+func (c *LRU[K, V]) Purge() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	for k, v := range c.items {
+		if c.onEvict != nil {
+			c.onEvict(k, v.Value)
+		}
+		delete(c.items, k)
+	}
+	for _, b := range c.buckets {
+		for _, ent := range b.entries {
+			delete(b.entries, ent.Key)
+		}
+	}
+	c.evictList.Init()
+}
+
+// Add adds a value to the cache. Returns true if an eviction occurred.
+// Returns false if there was no eviction: the item was already in the cache,
+// or the size was not exceeded.
+func (c *LRU[K, V]) Add(key K, value V) (evicted bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	now := time.Now()
+
+	// Check for existing item
+	if ent, ok := c.items[key]; ok {
+		c.evictList.MoveToFront(ent)
+		c.removeFromBucket(ent) // remove the entry from its current bucket as expiresAt is renewed
+		ent.Value = value
+		ent.ExpiresAt = now.Add(c.ttl)
+		c.addToBucket(ent)
+		return false
+	}
+
+	// Add new item
+	ent := c.evictList.PushFrontExpirable(key, value, now.Add(c.ttl))
+	c.items[key] = ent
+	c.addToBucket(ent) // adds the entry to the appropriate bucket and sets entry.expireBucket
+
+	evict := c.size > 0 && c.evictList.Length() > c.size
+	// Verify size not exceeded
+	if evict {
+		c.removeOldest()
+	}
+	return evict
+}
+
+// Get looks up a key's value from the cache.
+func (c *LRU[K, V]) Get(key K) (value V, ok bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	var ent *Entry[K, V]
+	if ent, ok = c.items[key]; ok {
+		// Expired item check
+		if time.Now().After(ent.ExpiresAt) {
+			return value, false
+		}
+		c.evictList.MoveToFront(ent)
+		return ent.Value, true
+	}
+	return
+}
+
+// Contains checks if a key is in the cache, without updating the recent-ness
+// or deleting it for being stale.
+func (c *LRU[K, V]) Contains(key K) (ok bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	_, ok = c.items[key]
+	return ok
+}
+
+// Peek returns the key value (or undefined if not found) without updating
+// the "recently used"-ness of the key.
+func (c *LRU[K, V]) Peek(key K) (value V, ok bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	var ent *Entry[K, V]
+	if ent, ok = c.items[key]; ok {
+		// Expired item check
+		if time.Now().After(ent.ExpiresAt) {
+			return value, false
+		}
+		return ent.Value, true
+	}
+	return
+}
+
+// Remove removes the provided key from the cache, returning if the
+// key was contained.
+func (c *LRU[K, V]) Remove(key K) bool {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if ent, ok := c.items[key]; ok {
+		c.removeElement(ent)
+		return true
+	}
+	return false
+}
+
+// RemoveOldest removes the oldest item from the cache.
+func (c *LRU[K, V]) RemoveOldest() (key K, value V, ok bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if ent := c.evictList.Back(); ent != nil {
+		c.removeElement(ent)
+		return ent.Key, ent.Value, true
+	}
+	return
+}
+
+// GetOldest returns the oldest entry
+func (c *LRU[K, V]) GetOldest() (key K, value V, ok bool) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if ent := c.evictList.Back(); ent != nil {
+		return ent.Key, ent.Value, true
+	}
+	return
+}
+
+func (c *LRU[K, V]) KeyValues() map[K]V {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	maps := make(map[K]V)
+	now := time.Now()
+	for ent := c.evictList.Back(); ent != nil; ent = ent.PrevEntry() {
+		if now.After(ent.ExpiresAt) {
+			continue
+		}
+		maps[ent.Key] = ent.Value
+		//keys = append(keys, ent.Key)
+	}
+	return maps
+}
+
+// Keys returns a slice of the keys in the cache, from oldest to newest.
+// Expired entries are filtered out.
+func (c *LRU[K, V]) Keys() []K {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	keys := make([]K, 0, len(c.items))
+	now := time.Now()
+	for ent := c.evictList.Back(); ent != nil; ent = ent.PrevEntry() {
+		if now.After(ent.ExpiresAt) {
+			continue
+		}
+		keys = append(keys, ent.Key)
+	}
+	return keys
+}
+
+// Values returns a slice of the values in the cache, from oldest to newest.
+// Expired entries are filtered out.
+func (c *LRU[K, V]) Values() []V {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	values := make([]V, 0, len(c.items))
+	now := time.Now()
+	for ent := c.evictList.Back(); ent != nil; ent = ent.PrevEntry() {
+		if now.After(ent.ExpiresAt) {
+			continue
+		}
+		values = append(values, ent.Value)
+	}
+	return values
+}
+
+// Len returns the number of items in the cache.
+func (c *LRU[K, V]) Len() int {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	return c.evictList.Length()
+}
+
+// Resize changes the cache size. Size of 0 means unlimited.
+func (c *LRU[K, V]) Resize(size int) (evicted int) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	if size <= 0 {
+		c.size = 0
+		return 0
+	}
+	diff := c.evictList.Length() - size
+	if diff < 0 {
+		diff = 0
+	}
+	for i := 0; i < diff; i++ {
+		c.removeOldest()
+	}
+	c.size = size
+	return diff
+}
+
+// Close destroys cleanup goroutine. To clean up the cache, run Purge() before Close().
+// func (c *LRU[K, V]) Close() {
+//	c.mu.Lock()
+//	defer c.mu.Unlock()
+//	select {
+//	case <-c.done:
+//		return
+//	default:
+//	}
+//	close(c.done)
+// }
+
+// removeOldest removes the oldest item from the cache. Has to be called with lock!
+func (c *LRU[K, V]) removeOldest() {
+	if ent := c.evictList.Back(); ent != nil {
+		c.removeElement(ent)
+	}
+}
+
+// removeElement is used to remove a given list element from the cache. Has to be called with lock!
+func (c *LRU[K, V]) removeElement(e *Entry[K, V]) {
+	c.evictList.Remove(e)
+	delete(c.items, e.Key)
+	c.removeFromBucket(e)
+	if c.onEvict != nil {
+		c.onEvict(e.Key, e.Value)
+	}
+}
+
+// deleteExpired deletes expired records from the oldest bucket, waiting for the newest entry
+// in it to expire first.
+func (c *LRU[K, V]) deleteExpired() {
+	c.mu.Lock()
+	bucketIdx := c.nextCleanupBucket
+	timeToExpire := time.Until(c.buckets[bucketIdx].newestEntry)
+	// wait for newest entry to expire before cleanup without holding lock
+	if timeToExpire > 0 {
+		c.mu.Unlock()
+		time.Sleep(timeToExpire)
+		c.mu.Lock()
+	}
+	for _, ent := range c.buckets[bucketIdx].entries {
+		c.removeElement(ent)
+	}
+	c.nextCleanupBucket = (c.nextCleanupBucket + 1) % numBuckets
+	c.mu.Unlock()
+}
+
+// addToBucket adds entry to expire bucket so that it will be cleaned up when the time comes. Has to be called with lock!
+func (c *LRU[K, V]) addToBucket(e *Entry[K, V]) {
+	bucketID := (numBuckets + c.nextCleanupBucket - 1) % numBuckets
+	e.ExpireBucket = bucketID
+	c.buckets[bucketID].entries[e.Key] = e
+	if c.buckets[bucketID].newestEntry.Before(e.ExpiresAt) {
+		c.buckets[bucketID].newestEntry = e.ExpiresAt
+	}
+}
+
+// removeFromBucket removes the entry from its corresponding bucket. Has to be called with lock!
+func (c *LRU[K, V]) removeFromBucket(e *Entry[K, V]) {
+	delete(c.buckets[e.ExpireBucket].entries, e.Key)
+}
+
+// Cap returns the capacity of the cache
+func (c *LRU[K, V]) Cap() int {
+	return c.size
+}
+
+// Entry is an LRU Entry
+type Entry[K comparable, V any] struct {
+	// Next and previous pointers in the doubly-linked list of elements.
+	// To simplify the implementation, internally a list l is implemented
+	// as a ring, such that &l.root is both the next element of the last
+	// list element (l.Back()) and the previous element of the first list
+	// element (l.Front()).
+	next, prev *Entry[K, V]
+
+	// The list to which this element belongs.
+	list *LruList[K, V]
+
+	// The LRU Key of this element.
+	Key K
+
+	// The Value stored with this element.
+	Value V
+
+	// The time this element would be cleaned up, optional
+	ExpiresAt time.Time
+
+	// The expiry bucket item was put in, optional
+	ExpireBucket uint8
+}
+
+// PrevEntry returns the previous list element or nil.
+func (e *Entry[K, V]) PrevEntry() *Entry[K, V] {
+	if p := e.prev; e.list != nil && p != &e.list.root {
+		return p
+	}
+	return nil
+}
+
+// LruList represents a doubly linked list.
+// The zero Value for LruList is an empty list ready to use.
+type LruList[K comparable, V any] struct {
+	root Entry[K, V] // sentinel list element, only &root, root.prev, and root.next are used
+	len  int         // current list Length excluding (this) sentinel element
+}
+
+// Init initializes or clears list l.
+func (l *LruList[K, V]) Init() *LruList[K, V] {
+	l.root.next = &l.root
+	l.root.prev = &l.root
+	l.len = 0
+	return l
+}
+
+// NewList returns an initialized list.
+func NewList[K comparable, V any]() *LruList[K, V] { return new(LruList[K, V]).Init() }
+
+// Length returns the number of elements of list l.
+// The complexity is O(1).
+func (l *LruList[K, V]) Length() int { return l.len }
+
+// Back returns the last element of list l or nil if the list is empty.
+func (l *LruList[K, V]) Back() *Entry[K, V] {
+	if l.len == 0 {
+		return nil
+	}
+	return l.root.prev
+}
+
+// lazyInit lazily initializes a zero List Value.
+func (l *LruList[K, V]) lazyInit() {
+	if l.root.next == nil {
+		l.Init()
+	}
+}
+
+// insert inserts e after at, increments l.len, and returns e.
+func (l *LruList[K, V]) insert(e, at *Entry[K, V]) *Entry[K, V] {
+	e.prev = at
+	e.next = at.next
+	e.prev.next = e
+	e.next.prev = e
+	e.list = l
+	l.len++
+	return e
+}
+
+// insertValue is a convenience wrapper for insert(&Entry{Value: v, ExpiresAt: ExpiresAt}, at).
+func (l *LruList[K, V]) insertValue(k K, v V, expiresAt time.Time, at *Entry[K, V]) *Entry[K, V] {
+	return l.insert(&Entry[K, V]{Value: v, Key: k, ExpiresAt: expiresAt}, at)
+}
+
+// Remove removes e from its list, decrements l.len
+func (l *LruList[K, V]) Remove(e *Entry[K, V]) V {
+	e.prev.next = e.next
+	e.next.prev = e.prev
+	e.next = nil // avoid memory leaks
+	e.prev = nil // avoid memory leaks
+	e.list = nil
+	l.len--
+
+	return e.Value
+}
+
+// move moves e to next to at.
+func (l *LruList[K, V]) move(e, at *Entry[K, V]) {
+	if e == at {
+		return
+	}
+	e.prev.next = e.next
+	e.next.prev = e.prev
+
+	e.prev = at
+	e.next = at.next
+	e.prev.next = e
+	e.next.prev = e
+}
+
+// PushFront inserts a new element e with value v at the front of list l and returns e.
+func (l *LruList[K, V]) PushFront(k K, v V) *Entry[K, V] {
+	l.lazyInit()
+	return l.insertValue(k, v, time.Time{}, &l.root)
+}
+
+// PushFrontExpirable inserts a new expirable element e with Value v at the front of list l and returns e.
+func (l *LruList[K, V]) PushFrontExpirable(k K, v V, expiresAt time.Time) *Entry[K, V] {
+	l.lazyInit()
+	return l.insertValue(k, v, expiresAt, &l.root)
+}
+
+// MoveToFront moves element e to the front of list l.
+// If e is not an element of l, the list is not modified.
+// The element must not be nil.
+func (l *LruList[K, V]) MoveToFront(e *Entry[K, V]) {
+	if e.list != l || l.root.next == e {
+		return
+	}
+	// see comment in List.Remove about initialization of l
+	l.move(e, &l.root)
+}

prepare_stmt.go

@@ -5,8 +5,10 @@ import (
 	"database/sql"
 	"database/sql/driver"
 	"errors"
+	"fmt"
 	"reflect"
 	"sync"
+	"time"
 )
 
 type Stmt struct {
@@ -17,16 +19,26 @@ type Stmt struct {
 }
 
 type PreparedStmtDB struct {
-	Stmts map[string]*Stmt
+	Stmts StmtStore
 	Mux   *sync.RWMutex
 	ConnPool
 }
 
-func NewPreparedStmtDB(connPool ConnPool) *PreparedStmtDB {
+func NewPreparedStmtDB(connPool ConnPool, prepareStmtLruConfig *PrepareStmtLruConfig) *PreparedStmtDB {
 	return &PreparedStmtDB{
 		ConnPool: connPool,
-		Stmts:    make(map[string]*Stmt),
+		Stmts: func() StmtStore {
-		Mux:      &sync.RWMutex{},
+			var stmts StmtStore
+			if prepareStmtLruConfig != nil && prepareStmtLruConfig.Open {
+				lru := &LruStmtStore{}
+				lru.NewLru(prepareStmtLruConfig.Size, prepareStmtLruConfig.TTL)
+				stmts = lru
+			} else {
+				stmts = &DefaultStmtStore{}
+			}
+			return stmts
+		}(),
+		Mux: &sync.RWMutex{},
 	}
 }
 
@@ -46,7 +58,7 @@ func (db *PreparedStmtDB) Close() {
 	db.Mux.Lock()
 	defer db.Mux.Unlock()
 
-	for _, stmt := range db.Stmts {
+	for _, stmt := range db.Stmts.AllMap() {
 		go func(s *Stmt) {
 			// make sure the stmt must finish preparation first
 			<-s.prepared
@@ -63,7 +75,7 @@ func (sdb *PreparedStmtDB) Reset() {
 	sdb.Mux.Lock()
 	defer sdb.Mux.Unlock()
 
-	for _, stmt := range sdb.Stmts {
+	for _, stmt := range sdb.Stmts.AllMap() {
 		go func(s *Stmt) {
 			// make sure the stmt must finish preparation first
 			<-s.prepared
@@ -72,12 +84,12 @@ func (sdb *PreparedStmtDB) Reset() {
 			}
 		}(stmt)
 	}
-	sdb.Stmts = make(map[string]*Stmt)
+	sdb.Stmts = &DefaultStmtStore{}
 }
 
 func (db *PreparedStmtDB) prepare(ctx context.Context, conn ConnPool, isTransaction bool, query string) (Stmt, error) {
 	db.Mux.RLock()
-	if stmt, ok := db.Stmts[query]; ok && (!stmt.Transaction || isTransaction) {
+	if stmt, ok := db.Stmts.Get(query); ok && (!stmt.Transaction || isTransaction) {
 		db.Mux.RUnlock()
 		// wait for other goroutines prepared
 		<-stmt.prepared
@@ -91,7 +103,7 @@ func (db *PreparedStmtDB) prepare(ctx context.Context, conn ConnPool, isTransact
 
 	db.Mux.Lock()
 	// double check
-	if stmt, ok := db.Stmts[query]; ok && (!stmt.Transaction || isTransaction) {
+	if stmt, ok := db.Stmts.Get(query); ok && (!stmt.Transaction || isTransaction) {
 		db.Mux.Unlock()
 		// wait for other goroutines prepared
 		<-stmt.prepared
@@ -109,7 +121,7 @@ func (db *PreparedStmtDB) prepare(ctx context.Context, conn ConnPool, isTransact
 	}
 	// cache preparing stmt first
 	cacheStmt := Stmt{Transaction: isTransaction, prepared: make(chan struct{})}
-	db.Stmts[query] = &cacheStmt
+	db.Stmts.Set(query, &cacheStmt)
 	db.Mux.Unlock()
 
 	// prepare completed
@@ -124,7 +136,8 @@ func (db *PreparedStmtDB) prepare(ctx context.Context, conn ConnPool, isTransact
 	if err != nil {
 		cacheStmt.prepareErr = err
 		db.Mux.Lock()
-		delete(db.Stmts, query)
+		db.Stmts.Delete(query)
+		//delete(db.Stmts.AllMap(), query)
 		db.Mux.Unlock()
 		return Stmt{}, err
 	}
@@ -165,7 +178,8 @@ func (db *PreparedStmtDB) ExecContext(ctx context.Context, query string, args ..
 			db.Mux.Lock()
 			defer db.Mux.Unlock()
 			go stmt.Close()
-			delete(db.Stmts, query)
+			db.Stmts.Delete(query)
+			//delete(db.Stmts.AllMap(), query)
 		}
 	}
 	return result, err
@@ -180,7 +194,8 @@ func (db *PreparedStmtDB) QueryContext(ctx context.Context, query string, args .
 			defer db.Mux.Unlock()
 
 			go stmt.Close()
-			delete(db.Stmts, query)
+			db.Stmts.Delete(query)
+			//delete(db.Stmts.AllMap(), query)
 		}
 	}
 	return rows, err
@@ -234,7 +249,8 @@ func (tx *PreparedStmtTX) ExecContext(ctx context.Context, query string, args ..
 			defer tx.PreparedStmtDB.Mux.Unlock()
 
 			go stmt.Close()
-			delete(tx.PreparedStmtDB.Stmts, query)
+			tx.PreparedStmtDB.Stmts.Delete(query)
+			//delete(tx.PreparedStmtDB.Stmts.AllMap(), query)
 		}
 	}
 	return result, err
@@ -249,7 +265,8 @@ func (tx *PreparedStmtTX) QueryContext(ctx context.Context, query string, args .
 			defer tx.PreparedStmtDB.Mux.Unlock()
 
 			go stmt.Close()
-			delete(tx.PreparedStmtDB.Stmts, query)
+			tx.PreparedStmtDB.Stmts.Delete(query)
+			//delete(tx.PreparedStmtDB.Stmts.AllMap(), query)
 		}
 	}
 	return rows, err
@@ -270,3 +287,66 @@ func (tx *PreparedStmtTX) Ping() error {
 	}
 	return conn.Ping()
 }
+
+type StmtStore interface {
+	Get(key string) (*Stmt, bool)
+	Set(key string, value *Stmt)
+	Delete(key string)
+	AllMap() map[string]*Stmt
+}
+
+// 默认的 map 实现
+type DefaultStmtStore struct {
+	defaultStmt map[string]*Stmt
+}
+
+func (s *DefaultStmtStore) AllMap() map[string]*Stmt {
+	return s.defaultStmt
+}
+func (s *DefaultStmtStore) Get(key string) (*Stmt, bool) {
+	stmt, ok := s.defaultStmt[key]
+	return stmt, ok
+}
+
+func (s *DefaultStmtStore) Set(key string, value *Stmt) {
+	s.defaultStmt[key] = value
+}
+
+func (s *DefaultStmtStore) Delete(key string) {
+	delete(s.defaultStmt, key)
+}
+
+type LruStmtStore struct {
+	lru *LRU[string, *Stmt]
+}
+
+func (s *LruStmtStore) NewLru(size int, ttl time.Duration) {
+	onEvicted := func(k string, v *Stmt) {
+		if v != nil {
+			go func() {
+				err := v.Close()
+				if err != nil {
+					//
+					fmt.Print("close stmt err: ", err.Error())
+				}
+			}()
+		}
+	}
+	s.lru = NewLRU[string, *Stmt](size, onEvicted, ttl)
+}
+
+func (s *LruStmtStore) AllMap() map[string]*Stmt {
+	return s.lru.KeyValues()
+}
+func (s *LruStmtStore) Get(key string) (*Stmt, bool) {
+	stmt, ok := s.lru.Get(key)
+	return stmt, ok
+}
+
+func (s *LruStmtStore) Set(key string, value *Stmt) {
+	s.lru.Add(key, value)
+}
+
+func (s *LruStmtStore) Delete(key string) {
+	s.lru.Remove(key)
+}