generate db if not exists when select

put TTL checker in associated db too

config/config.go

@@ -214,10 +214,7 @@ func (cfg *Config) adjust() {
 	cfg.ConnReadBufferSize = getDefault(4*KB, cfg.ConnReadBufferSize)
 	cfg.ConnWriteBufferSize = getDefault(4*KB, cfg.ConnWriteBufferSize)
 	cfg.TTLCheckInterval = getDefault(1, cfg.TTLCheckInterval)
-	cfg.Databases = getDefault(0, cfg.Databases)
-	if cfg.Databases > 16 {
-		cfg.Databases = 16
-	}
+	cfg.Databases = getDefault(16, cfg.Databases)
 }
 
 func (cfg *LevelDBConfig) adjust() {

ledis/const.go

@@ -104,6 +104,8 @@ var (
 )
 
 const (
+	MaxDatabases int = 16
+
 	//max key size
 	MaxKeySize int = 1024
 
@@ -127,11 +129,11 @@ var (
 	ErrRplNotSupport = errors.New("replication not support")
 )
 
-const (
-	DBAutoCommit    uint8 = 0x0
-	DBInTransaction uint8 = 0x1
-	DBInMulti       uint8 = 0x2
-)
+// const (
+// 	DBAutoCommit    uint8 = 0x0
+// 	DBInTransaction uint8 = 0x1
+// 	DBInMulti       uint8 = 0x2
+// )
 
 const (
 	BitAND = "and"

ledis/ledis.go

@@ -18,7 +18,9 @@ type Ledis struct {
 	cfg *config.Config
 
 	ldb *store.DB
-	dbs []*DB
+
+	dbLock sync.Mutex
+	dbs    map[int]*DB
 
 	quit chan struct{}
 	wg   sync.WaitGroup
@@ -35,7 +37,8 @@ type Ledis struct {
 
 	lock io.Closer
 
-	tcs []*ttlChecker
+	ttlCheckers  []*ttlChecker
+	ttlCheckerCh chan *ttlChecker
 }
 
 func Open(cfg *config.Config) (*Ledis, error) {
@@ -84,10 +87,7 @@ func Open(cfg *config.Config) (*Ledis, error) {
 		l.r = nil
 	}
 
-	l.dbs = make([]*DB, cfg.Databases)
-	for i := 0; i < cfg.Databases; i++ {
-		l.dbs[i] = l.newDB(uint8(i))
-	}
+	l.dbs = make(map[int]*DB, 16)
 
 	l.checkTTL()
 
@@ -112,11 +112,26 @@ func (l *Ledis) Close() {
 }
 
 func (l *Ledis) Select(index int) (*DB, error) {
-	if index < 0 || index >= len(l.dbs) {
-		return nil, fmt.Errorf("invalid db index %d, must in [0, %d]", index, len(l.dbs)-1)
+	if index < 0 || index >= MaxDatabases {
+		return nil, fmt.Errorf("invalid db index %d, must in [0, %d]", index, MaxDatabases-1)
 	}
 
-	return l.dbs[index], nil
+	l.dbLock.Lock()
+	defer l.dbLock.Unlock()
+
+	db, ok := l.dbs[index]
+	if ok {
+		return db, nil
+	}
+
+	db = l.newDB(index)
+	l.dbs[index] = db
+
+	go func(db *DB) {
+		l.ttlCheckerCh <- db.ttlChecker
+	}(db)
+
+	return db, nil
 }
 
 // Flush All will clear all data and replication logs
@@ -176,19 +191,8 @@ func (l *Ledis) IsReadOnly() bool {
 }
 
 func (l *Ledis) checkTTL() {
-	l.tcs = make([]*ttlChecker, len(l.dbs))
-	for i, db := range l.dbs {
-		c := newTTLChecker(db)
-
-		c.register(KVType, db.kvBatch, db.delete)
-		c.register(ListType, db.listBatch, db.lDelete)
-		c.register(HashType, db.hashBatch, db.hDelete)
-		c.register(ZSetType, db.zsetBatch, db.zDelete)
-		//		c.register(BitType, db.binBatch, db.bDelete)
-		c.register(SetType, db.setBatch, db.sDelete)
-
-		l.tcs[i] = c
-	}
+	l.ttlCheckers = make([]*ttlChecker, 0, 16)
+	l.ttlCheckerCh = make(chan *ttlChecker, 16)
 
 	if l.cfg.TTLCheckInterval == 0 {
 		l.cfg.TTLCheckInterval = 1
@@ -208,9 +212,12 @@ func (l *Ledis) checkTTL() {
 					break
 				}
 
-				for _, c := range l.tcs {
+				for _, c := range l.ttlCheckers {
 					c.check()
 				}
+			case c := <-l.ttlCheckerCh:
+				l.ttlCheckers = append(l.ttlCheckers, c)
+				c.check()
 			case <-l.quit:
 				return
 			}

ledis/ledis_db.go

@@ -39,12 +39,14 @@ type DB struct {
 	//	binBatch  *batch
 	setBatch *batch
 
-	status uint8
+	// status uint8
+
+	ttlChecker *ttlChecker
 
 	lbkeys *lBlockKeys
 }
 
-func (l *Ledis) newDB(index uint8) *DB {
+func (l *Ledis) newDB(index int) *DB {
 	d := new(DB)
 
 	d.l = l
@@ -53,8 +55,8 @@ func (l *Ledis) newDB(index uint8) *DB {
 
 	d.bucket = d.sdb
 
-	d.status = DBAutoCommit
-	d.index = index
+	//	d.status = DBAutoCommit
+	d.index = uint8(index)
 
 	d.kvBatch = d.newBatch()
 	d.listBatch = d.newBatch()
@@ -65,9 +67,28 @@ func (l *Ledis) newDB(index uint8) *DB {
 
 	d.lbkeys = newLBlockKeys()
 
+	d.ttlChecker = d.newTTLChecker()
+
 	return d
 }
 
+func (db *DB) newTTLChecker() *ttlChecker {
+	c := new(ttlChecker)
+	c.db = db
+	c.txs = make([]*batch, maxDataType)
+	c.cbs = make([]onExpired, maxDataType)
+	c.nc = 0
+
+	c.register(KVType, db.kvBatch, db.delete)
+	c.register(ListType, db.listBatch, db.lDelete)
+	c.register(HashType, db.hashBatch, db.hDelete)
+	c.register(ZSetType, db.zsetBatch, db.zDelete)
+	//		c.register(BitType, db.binBatch, db.bDelete)
+	c.register(SetType, db.setBatch, db.sDelete)
+
+	return c
+}
+
 func (db *DB) newBatch() *batch {
 	return db.l.newBatch(db.bucket.NewWriteBatch(), &dbBatchLocker{l: &sync.Mutex{}, wrLock: &db.l.wLock})
 }
@@ -76,9 +97,9 @@ func (db *DB) Index() int {
 	return int(db.index)
 }
 
-func (db *DB) IsAutoCommit() bool {
-	return db.status == DBAutoCommit
-}
+// func (db *DB) IsAutoCommit() bool {
+// 	return db.status == DBAutoCommit
+// }
 
 func (db *DB) FlushAll() (drop int64, err error) {
 	all := [...](func() (int64, error)){

ledis/t_list.go

@@ -521,13 +521,10 @@ func (db *DB) lblockPop(keys [][]byte, whereSeq int32, timeout time.Duration) ([
 		} else if v != nil {
 			return []interface{}{key, v}, nil
 		} else {
-			if db.IsAutoCommit() {
-				//block wait can not be supported in transaction and multi
 			db.lbkeys.wait(key, ch)
 			bkeys = append(bkeys, key)
 		}
 	}
-	}
 	if len(bkeys) == 0 {
 		return nil, nil
 	}
@@ -575,12 +572,6 @@ func (db *DB) lblockPop(keys [][]byte, whereSeq int32, timeout time.Duration) ([
 }
 
 func (db *DB) lSignalAsReady(key []byte, num int) {
-	if db.status == DBInTransaction {
-		//for transaction, only data can be pushed after tx commit and it is hard to signal
-		//so we don't handle it now
-		return
-	}
-
 	db.lbkeys.signal(key, num)
 }
 

ledis/t_ttl.go

@@ -85,8 +85,7 @@ func (db *DB) expireAt(t *batch, dataType byte, key []byte, when int64) {
 	t.Put(tk, mk)
 	t.Put(mk, PutInt64(when))
 
-	tc := db.l.tcs[db.index]
-	tc.setNextCheckTime(when, false)
+	db.ttlChecker.setNextCheckTime(when, false)
 }
 
 func (db *DB) ttl(dataType byte, key []byte) (t int64, err error) {
@@ -121,15 +120,6 @@ func (db *DB) rmExpire(t *batch, dataType byte, key []byte) (int64, error) {
 	}
 }
 
-func newTTLChecker(db *DB) *ttlChecker {
-	c := new(ttlChecker)
-	c.db = db
-	c.txs = make([]*batch, maxDataType)
-	c.cbs = make([]onExpired, maxDataType)
-	c.nc = 0
-	return c
-}
-
 func (c *ttlChecker) register(dataType byte, t *batch, f onExpired) {
 	c.txs[dataType] = t
 	c.cbs[dataType] = f