Merge pull request #780 from go-redis/fix/pool-cleanup

Fix/pool cleanup

cluster.go

@@ -1172,7 +1172,7 @@ func (c *ClusterClient) defaultProcessPipeline(cmds []Cmder) error {
 		failedCmds := make(map[*clusterNode][]Cmder)
 
 		for node, cmds := range cmdsMap {
-			cn, _, err := node.Client.getConn()
+			cn, err := node.Client.getConn()
 			if err != nil {
 				if err == pool.ErrClosed {
 					c.remapCmds(cmds, failedCmds)
@@ -1184,9 +1184,9 @@ func (c *ClusterClient) defaultProcessPipeline(cmds []Cmder) error {
 
 			err = c.pipelineProcessCmds(node, cn, cmds, failedCmds)
 			if err == nil || internal.IsRedisError(err) {
-				_ = node.Client.connPool.Put(cn)
+				node.Client.connPool.Put(cn)
 			} else {
-				_ = node.Client.connPool.Remove(cn)
+				node.Client.connPool.Remove(cn)
 			}
 		}
 
@@ -1336,7 +1336,7 @@ func (c *ClusterClient) defaultProcessTxPipeline(cmds []Cmder) error {
 			failedCmds := make(map[*clusterNode][]Cmder)
 
 			for node, cmds := range cmdsMap {
-				cn, _, err := node.Client.getConn()
+				cn, err := node.Client.getConn()
 				if err != nil {
 					if err == pool.ErrClosed {
 						c.remapCmds(cmds, failedCmds)
@@ -1348,9 +1348,9 @@ func (c *ClusterClient) defaultProcessTxPipeline(cmds []Cmder) error {
 
 				err = c.txPipelineProcessCmds(node, cn, cmds, failedCmds)
 				if err == nil || internal.IsRedisError(err) {
-					_ = node.Client.connPool.Put(cn)
+					node.Client.connPool.Put(cn)
 				} else {
-					_ = node.Client.connPool.Remove(cn)
+					node.Client.connPool.Remove(cn)
 				}
 			}
 

internal/pool/bench_test.go

@@ -20,13 +20,11 @@ func benchmarkPoolGetPut(b *testing.B, poolSize int) {
 
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
-			cn, _, err := connPool.Get()
+			cn, err := connPool.Get()
 			if err != nil {
 				b.Fatal(err)
 			}
-			if err = connPool.Put(cn); err != nil {
-				b.Fatal(err)
-			}
+			connPool.Put(cn)
 		}
 	})
 }
@@ -56,13 +54,11 @@ func benchmarkPoolGetRemove(b *testing.B, poolSize int) {
 
 	b.RunParallel(func(pb *testing.PB) {
 		for pb.Next() {
-			cn, _, err := connPool.Get()
+			cn, err := connPool.Get()
 			if err != nil {
 				b.Fatal(err)
 			}
-			if err := connPool.Remove(cn); err != nil {
-				b.Fatal(err)
-			}
+			connPool.Remove(cn)
 		}
 	})
 }

internal/pool/pool.go

@@ -28,7 +28,8 @@ type Stats struct {
 	Timeouts uint32 // number of times a wait timeout occurred
 
 	TotalConns uint32 // number of total connections in the pool
-	FreeConns  uint32 // number of free connections in the pool
+	FreeConns  uint32 // deprecated - use IdleConns
+	IdleConns  uint32 // number of idle connections in the pool
 	StaleConns uint32 // number of stale connections removed from the pool
 }
 
@@ -36,12 +37,12 @@ type Pooler interface {
 	NewConn() (*Conn, error)
 	CloseConn(*Conn) error
 
-	Get() (*Conn, bool, error)
-	Put(*Conn) error
-	Remove(*Conn) error
+	Get() (*Conn, error)
+	Put(*Conn)
+	Remove(*Conn)
 
 	Len() int
-	FreeLen() int
+	IdleLen() int
 	Stats() *Stats
 
 	Close() error
@@ -70,8 +71,8 @@ type ConnPool struct {
 	connsMu sync.Mutex
 	conns   []*Conn
 
-	freeConnsMu sync.Mutex
-	freeConns   []*Conn
+	idleConnsMu sync.RWMutex
+	idleConns   []*Conn
 
 	stats Stats
 
@@ -86,15 +87,29 @@ func NewConnPool(opt *Options) *ConnPool {
 
 		queue:     make(chan struct{}, opt.PoolSize),
 		conns:     make([]*Conn, 0, opt.PoolSize),
-		freeConns: make([]*Conn, 0, opt.PoolSize),
+		idleConns: make([]*Conn, 0, opt.PoolSize),
 	}
+
 	if opt.IdleTimeout > 0 && opt.IdleCheckFrequency > 0 {
 		go p.reaper(opt.IdleCheckFrequency)
 	}
+
 	return p
 }
 
 func (p *ConnPool) NewConn() (*Conn, error) {
+	cn, err := p.newConn()
+	if err != nil {
+		return nil, err
+	}
+
+	p.connsMu.Lock()
+	p.conns = append(p.conns, cn)
+	p.connsMu.Unlock()
+	return cn, nil
+}
+
+func (p *ConnPool) newConn() (*Conn, error) {
 	if p.closed() {
 		return nil, ErrClosed
 	}
@@ -112,12 +127,7 @@ func (p *ConnPool) NewConn() (*Conn, error) {
 		return nil, err
 	}
 
-	cn := NewConn(netConn)
-	p.connsMu.Lock()
-	p.conns = append(p.conns, cn)
-	p.connsMu.Unlock()
-
-	return cn, nil
+	return NewConn(netConn), nil
 }
 
 func (p *ConnPool) tryDial() {
@@ -153,34 +163,20 @@ func (p *ConnPool) getLastDialError() error {
 }
 
 // Get returns existed connection from the pool or creates a new one.
-func (p *ConnPool) Get() (*Conn, bool, error) {
+func (p *ConnPool) Get() (*Conn, error) {
 	if p.closed() {
-		return nil, false, ErrClosed
+		return nil, ErrClosed
 	}
 
-	select {
-	case p.queue <- struct{}{}:
-	default:
-		timer := timers.Get().(*time.Timer)
-		timer.Reset(p.opt.PoolTimeout)
-
-		select {
-		case p.queue <- struct{}{}:
-			if !timer.Stop() {
-				<-timer.C
-			}
-			timers.Put(timer)
-		case <-timer.C:
-			timers.Put(timer)
-			atomic.AddUint32(&p.stats.Timeouts, 1)
-			return nil, false, ErrPoolTimeout
-		}
+	err := p.waitTurn()
+	if err != nil {
+		return nil, err
 	}
 
 	for {
-		p.freeConnsMu.Lock()
-		cn := p.popFree()
-		p.freeConnsMu.Unlock()
+		p.idleConnsMu.Lock()
+		cn := p.popIdle()
+		p.idleConnsMu.Unlock()
 
 		if cn == nil {
 			break
@@ -192,50 +188,89 @@ func (p *ConnPool) Get() (*Conn, bool, error) {
 		}
 
 		atomic.AddUint32(&p.stats.Hits, 1)
-		return cn, false, nil
+		return cn, nil
 	}
 
 	atomic.AddUint32(&p.stats.Misses, 1)
 
 	newcn, err := p.NewConn()
 	if err != nil {
-		<-p.queue
-		return nil, false, err
+		p.freeTurn()
+		return nil, err
 	}
 
-	return newcn, true, nil
+	return newcn, nil
 }
 
-func (p *ConnPool) popFree() *Conn {
-	if len(p.freeConns) == 0 {
+func (p *ConnPool) getTurn() {
+	p.queue <- struct{}{}
+}
+
+func (p *ConnPool) waitTurn() error {
+	select {
+	case p.queue <- struct{}{}:
+		return nil
+	default:
+		timer := timers.Get().(*time.Timer)
+		timer.Reset(p.opt.PoolTimeout)
+
+		select {
+		case p.queue <- struct{}{}:
+			if !timer.Stop() {
+				<-timer.C
+			}
+			timers.Put(timer)
+			return nil
+		case <-timer.C:
+			timers.Put(timer)
+			atomic.AddUint32(&p.stats.Timeouts, 1)
+			return ErrPoolTimeout
+		}
+	}
+}
+
+func (p *ConnPool) freeTurn() {
+	<-p.queue
+}
+
+func (p *ConnPool) popIdle() *Conn {
+	if len(p.idleConns) == 0 {
 		return nil
 	}
 
-	idx := len(p.freeConns) - 1
-	cn := p.freeConns[idx]
-	p.freeConns = p.freeConns[:idx]
+	idx := len(p.idleConns) - 1
+	cn := p.idleConns[idx]
+	p.idleConns = p.idleConns[:idx]
+
 	return cn
 }
 
-func (p *ConnPool) Put(cn *Conn) error {
-	if data := cn.Rd.PeekBuffered(); data != nil {
-		internal.Logf("connection has unread data: %q", data)
-		return p.Remove(cn)
+func (p *ConnPool) Put(cn *Conn) {
+	buf := cn.Rd.PeekBuffered()
+	if buf != nil {
+		internal.Logf("connection has unread data: %.100q", buf)
+		p.Remove(cn)
+		return
 	}
-	p.freeConnsMu.Lock()
-	p.freeConns = append(p.freeConns, cn)
-	p.freeConnsMu.Unlock()
-	<-p.queue
-	return nil
+
+	p.idleConnsMu.Lock()
+	p.idleConns = append(p.idleConns, cn)
+	p.idleConnsMu.Unlock()
+	p.freeTurn()
 }
 
-func (p *ConnPool) Remove(cn *Conn) error {
-	_ = p.CloseConn(cn)
-	<-p.queue
-	return nil
+func (p *ConnPool) Remove(cn *Conn) {
+	p.removeConn(cn)
+	p.freeTurn()
+	_ = p.closeConn(cn)
 }
 
 func (p *ConnPool) CloseConn(cn *Conn) error {
+	p.removeConn(cn)
+	return p.closeConn(cn)
+}
+
+func (p *ConnPool) removeConn(cn *Conn) {
 	p.connsMu.Lock()
 	for i, c := range p.conns {
 		if c == cn {
@@ -244,8 +279,6 @@ func (p *ConnPool) CloseConn(cn *Conn) error {
 		}
 	}
 	p.connsMu.Unlock()
-
-	return p.closeConn(cn)
 }
 
 func (p *ConnPool) closeConn(cn *Conn) error {
@@ -263,22 +296,24 @@ func (p *ConnPool) Len() int {
 	return l
 }
 
-// FreeLen returns number of free connections.
-func (p *ConnPool) FreeLen() int {
-	p.freeConnsMu.Lock()
-	l := len(p.freeConns)
-	p.freeConnsMu.Unlock()
+// FreeLen returns number of idle connections.
+func (p *ConnPool) IdleLen() int {
+	p.idleConnsMu.RLock()
+	l := len(p.idleConns)
+	p.idleConnsMu.RUnlock()
 	return l
 }
 
 func (p *ConnPool) Stats() *Stats {
+	idleLen := p.IdleLen()
 	return &Stats{
 		Hits:     atomic.LoadUint32(&p.stats.Hits),
 		Misses:   atomic.LoadUint32(&p.stats.Misses),
 		Timeouts: atomic.LoadUint32(&p.stats.Timeouts),
 
 		TotalConns: uint32(p.Len()),
-		FreeConns:  uint32(p.FreeLen()),
+		FreeConns:  uint32(idleLen),
+		IdleConns:  uint32(idleLen),
 		StaleConns: atomic.LoadUint32(&p.stats.StaleConns),
 	}
 }
@@ -316,41 +351,45 @@ func (p *ConnPool) Close() error {
 	p.conns = nil
 	p.connsMu.Unlock()
 
-	p.freeConnsMu.Lock()
-	p.freeConns = nil
-	p.freeConnsMu.Unlock()
+	p.idleConnsMu.Lock()
+	p.idleConns = nil
+	p.idleConnsMu.Unlock()
 
 	return firstErr
 }
 
-func (p *ConnPool) reapStaleConn() bool {
-	if len(p.freeConns) == 0 {
-		return false
+func (p *ConnPool) reapStaleConn() *Conn {
+	if len(p.idleConns) == 0 {
+		return nil
 	}
 
-	cn := p.freeConns[0]
+	cn := p.idleConns[0]
 	if !cn.IsStale(p.opt.IdleTimeout) {
-		return false
+		return nil
 	}
 
-	p.CloseConn(cn)
-	p.freeConns = append(p.freeConns[:0], p.freeConns[1:]...)
+	p.idleConns = append(p.idleConns[:0], p.idleConns[1:]...)
 
-	return true
+	return cn
 }
 
 func (p *ConnPool) ReapStaleConns() (int, error) {
 	var n int
 	for {
-		p.queue <- struct{}{}
-		p.freeConnsMu.Lock()
+		p.getTurn()
 
-		reaped := p.reapStaleConn()
+		p.idleConnsMu.Lock()
+		cn := p.reapStaleConn()
+		p.idleConnsMu.Unlock()
 
-		p.freeConnsMu.Unlock()
-		<-p.queue
+		if cn != nil {
+			p.removeConn(cn)
+		}
 
-		if reaped {
+		p.freeTurn()
+
+		if cn != nil {
+			p.closeConn(cn)
 			n++
 		} else {
 			break

internal/pool/pool_single.go

@@ -20,29 +20,27 @@ func (p *SingleConnPool) CloseConn(*Conn) error {
 	panic("not implemented")
 }
 
-func (p *SingleConnPool) Get() (*Conn, bool, error) {
-	return p.cn, false, nil
+func (p *SingleConnPool) Get() (*Conn, error) {
+	return p.cn, nil
 }
 
-func (p *SingleConnPool) Put(cn *Conn) error {
+func (p *SingleConnPool) Put(cn *Conn) {
 	if p.cn != cn {
 		panic("p.cn != cn")
 	}
-	return nil
 }
 
-func (p *SingleConnPool) Remove(cn *Conn) error {
+func (p *SingleConnPool) Remove(cn *Conn) {
 	if p.cn != cn {
 		panic("p.cn != cn")
 	}
-	return nil
 }
 
 func (p *SingleConnPool) Len() int {
 	return 1
 }
 
-func (p *SingleConnPool) FreeLen() int {
+func (p *SingleConnPool) IdleLen() int {
 	return 0
 }
 

internal/pool/pool_sticky.go

@@ -28,55 +28,40 @@ func (p *StickyConnPool) CloseConn(*Conn) error {
 	panic("not implemented")
 }
 
-func (p *StickyConnPool) Get() (*Conn, bool, error) {
+func (p *StickyConnPool) Get() (*Conn, error) {
 	p.mu.Lock()
 	defer p.mu.Unlock()
 
 	if p.closed {
-		return nil, false, ErrClosed
+		return nil, ErrClosed
 	}
 	if p.cn != nil {
-		return p.cn, false, nil
+		return p.cn, nil
 	}
 
-	cn, _, err := p.pool.Get()
+	cn, err := p.pool.Get()
 	if err != nil {
-		return nil, false, err
+		return nil, err
 	}
+
 	p.cn = cn
-	return cn, true, nil
+	return cn, nil
 }
 
-func (p *StickyConnPool) putUpstream() (err error) {
-	err = p.pool.Put(p.cn)
+func (p *StickyConnPool) putUpstream() {
+	p.pool.Put(p.cn)
 	p.cn = nil
-	return err
 }
 
-func (p *StickyConnPool) Put(cn *Conn) error {
-	p.mu.Lock()
-	defer p.mu.Unlock()
+func (p *StickyConnPool) Put(cn *Conn) {}
 
-	if p.closed {
-		return ErrClosed
-	}
-	return nil
-}
-
-func (p *StickyConnPool) removeUpstream() error {
-	err := p.pool.Remove(p.cn)
+func (p *StickyConnPool) removeUpstream() {
+	p.pool.Remove(p.cn)
 	p.cn = nil
-	return err
 }
 
-func (p *StickyConnPool) Remove(cn *Conn) error {
-	p.mu.Lock()
-	defer p.mu.Unlock()
-
-	if p.closed {
-		return nil
-	}
-	return p.removeUpstream()
+func (p *StickyConnPool) Remove(cn *Conn) {
+	p.removeUpstream()
 }
 
 func (p *StickyConnPool) Len() int {
@@ -89,7 +74,7 @@ func (p *StickyConnPool) Len() int {
 	return 1
 }
 
-func (p *StickyConnPool) FreeLen() int {
+func (p *StickyConnPool) IdleLen() int {
 	p.mu.Lock()
 	defer p.mu.Unlock()
 
@@ -111,13 +96,14 @@ func (p *StickyConnPool) Close() error {
 		return ErrClosed
 	}
 	p.closed = true
-	var err error
+
 	if p.cn != nil {
 		if p.reusable {
-			err = p.putUpstream()
+			p.putUpstream()
 		} else {
-			err = p.removeUpstream()
+			p.removeUpstream()
 		}
 	}
-	return err
+
+	return nil
 }

internal/pool/pool_test.go

@@ -29,13 +29,13 @@ var _ = Describe("ConnPool", func() {
 
 	It("should unblock client when conn is removed", func() {
 		// Reserve one connection.
-		cn, _, err := connPool.Get()
+		cn, err := connPool.Get()
 		Expect(err).NotTo(HaveOccurred())
 
 		// Reserve all other connections.
 		var cns []*pool.Conn
 		for i := 0; i < 9; i++ {
-			cn, _, err := connPool.Get()
+			cn, err := connPool.Get()
 			Expect(err).NotTo(HaveOccurred())
 			cns = append(cns, cn)
 		}
@@ -46,12 +46,11 @@ var _ = Describe("ConnPool", func() {
 			defer GinkgoRecover()
 
 			started <- true
-			_, _, err := connPool.Get()
+			_, err := connPool.Get()
 			Expect(err).NotTo(HaveOccurred())
 			done <- true
 
-			err = connPool.Put(cn)
-			Expect(err).NotTo(HaveOccurred())
+			connPool.Put(cn)
 		}()
 		<-started
 
@@ -59,14 +58,13 @@ var _ = Describe("ConnPool", func() {
 		select {
 		case <-done:
 			Fail("Get is not blocked")
-		default:
+		case <-time.After(time.Millisecond):
 			// ok
 		}
 
-		err = connPool.Remove(cn)
-		Expect(err).NotTo(HaveOccurred())
+		connPool.Remove(cn)
 
-		// Check that Ping is unblocked.
+		// Check that Get is unblocked.
 		select {
 		case <-done:
 			// ok
@@ -75,8 +73,7 @@ var _ = Describe("ConnPool", func() {
 		}
 
 		for _, cn := range cns {
-			err = connPool.Put(cn)
-			Expect(err).NotTo(HaveOccurred())
+			connPool.Put(cn)
 		}
 	})
 })
@@ -107,7 +104,7 @@ var _ = Describe("conns reaper", func() {
 		// add stale connections
 		idleConns = nil
 		for i := 0; i < 3; i++ {
-			cn, _, err := connPool.Get()
+			cn, err := connPool.Get()
 			Expect(err).NotTo(HaveOccurred())
 			cn.SetUsedAt(time.Now().Add(-2 * idleTimeout))
 			conns = append(conns, cn)
@@ -116,17 +113,17 @@ var _ = Describe("conns reaper", func() {
 
 		// add fresh connections
 		for i := 0; i < 3; i++ {
-			cn, _, err := connPool.Get()
+			cn, err := connPool.Get()
 			Expect(err).NotTo(HaveOccurred())
 			conns = append(conns, cn)
 		}
 
 		for _, cn := range conns {
-			Expect(connPool.Put(cn)).NotTo(HaveOccurred())
+			connPool.Put(cn)
 		}
 
 		Expect(connPool.Len()).To(Equal(6))
-		Expect(connPool.FreeLen()).To(Equal(6))
+		Expect(connPool.IdleLen()).To(Equal(6))
 
 		n, err := connPool.ReapStaleConns()
 		Expect(err).NotTo(HaveOccurred())
@@ -136,14 +133,14 @@ var _ = Describe("conns reaper", func() {
 	AfterEach(func() {
 		_ = connPool.Close()
 		Expect(connPool.Len()).To(Equal(0))
-		Expect(connPool.FreeLen()).To(Equal(0))
+		Expect(connPool.IdleLen()).To(Equal(0))
 		Expect(len(closedConns)).To(Equal(len(conns)))
 		Expect(closedConns).To(ConsistOf(conns))
 	})
 
 	It("reaps stale connections", func() {
 		Expect(connPool.Len()).To(Equal(3))
-		Expect(connPool.FreeLen()).To(Equal(3))
+		Expect(connPool.IdleLen()).To(Equal(3))
 	})
 
 	It("does not reap fresh connections", func() {
@@ -161,36 +158,34 @@ var _ = Describe("conns reaper", func() {
 		for j := 0; j < 3; j++ {
 			var freeCns []*pool.Conn
 			for i := 0; i < 3; i++ {
-				cn, _, err := connPool.Get()
+				cn, err := connPool.Get()
 				Expect(err).NotTo(HaveOccurred())
 				Expect(cn).NotTo(BeNil())
 				freeCns = append(freeCns, cn)
 			}
 
 			Expect(connPool.Len()).To(Equal(3))
-			Expect(connPool.FreeLen()).To(Equal(0))
+			Expect(connPool.IdleLen()).To(Equal(0))
 
-			cn, _, err := connPool.Get()
+			cn, err := connPool.Get()
 			Expect(err).NotTo(HaveOccurred())
 			Expect(cn).NotTo(BeNil())
 			conns = append(conns, cn)
 
 			Expect(connPool.Len()).To(Equal(4))
-			Expect(connPool.FreeLen()).To(Equal(0))
+			Expect(connPool.IdleLen()).To(Equal(0))
 
-			err = connPool.Remove(cn)
-			Expect(err).NotTo(HaveOccurred())
+			connPool.Remove(cn)
 
 			Expect(connPool.Len()).To(Equal(3))
-			Expect(connPool.FreeLen()).To(Equal(0))
+			Expect(connPool.IdleLen()).To(Equal(0))
 
 			for _, cn := range freeCns {
-				err := connPool.Put(cn)
-				Expect(err).NotTo(HaveOccurred())
+				connPool.Put(cn)
 			}
 
 			Expect(connPool.Len()).To(Equal(3))
-			Expect(connPool.FreeLen()).To(Equal(3))
+			Expect(connPool.IdleLen()).To(Equal(3))
 		}
 	})
 })
@@ -222,18 +217,18 @@ var _ = Describe("race", func() {
 
 		perform(C, func(id int) {
 			for i := 0; i < N; i++ {
-				cn, _, err := connPool.Get()
+				cn, err := connPool.Get()
 				Expect(err).NotTo(HaveOccurred())
 				if err == nil {
-					Expect(connPool.Put(cn)).NotTo(HaveOccurred())
+					connPool.Put(cn)
 				}
 			}
 		}, func(id int) {
 			for i := 0; i < N; i++ {
-				cn, _, err := connPool.Get()
+				cn, err := connPool.Get()
 				Expect(err).NotTo(HaveOccurred())
 				if err == nil {
-					Expect(connPool.Remove(cn)).NotTo(HaveOccurred())
+					connPool.Remove(cn)
 				}
 			}
 		})

options.go

@@ -68,8 +68,7 @@ type Options struct {
 	// Default is 5 minutes.
 	IdleTimeout time.Duration
 	// Frequency of idle checks.
-	// Default is 1 minute.
-	// When minus value is set, then idle check is disabled.
+	// Default is 1 minute. -1 disables idle check.
 	IdleCheckFrequency time.Duration
 
 	// Enables read only queries on slave nodes.

pool_test.go

@@ -30,8 +30,8 @@ var _ = Describe("pool", func() {
 
 		pool := client.Pool()
 		Expect(pool.Len()).To(BeNumerically("<=", 10))
-		Expect(pool.FreeLen()).To(BeNumerically("<=", 10))
-		Expect(pool.Len()).To(Equal(pool.FreeLen()))
+		Expect(pool.IdleLen()).To(BeNumerically("<=", 10))
+		Expect(pool.Len()).To(Equal(pool.IdleLen()))
 	})
 
 	It("respects max size on multi", func() {
@@ -55,8 +55,8 @@ var _ = Describe("pool", func() {
 
 		pool := client.Pool()
 		Expect(pool.Len()).To(BeNumerically("<=", 10))
-		Expect(pool.FreeLen()).To(BeNumerically("<=", 10))
-		Expect(pool.Len()).To(Equal(pool.FreeLen()))
+		Expect(pool.IdleLen()).To(BeNumerically("<=", 10))
+		Expect(pool.Len()).To(Equal(pool.IdleLen()))
 	})
 
 	It("respects max size on pipelines", func() {
@@ -73,15 +73,15 @@ var _ = Describe("pool", func() {
 
 		pool := client.Pool()
 		Expect(pool.Len()).To(BeNumerically("<=", 10))
-		Expect(pool.FreeLen()).To(BeNumerically("<=", 10))
-		Expect(pool.Len()).To(Equal(pool.FreeLen()))
+		Expect(pool.IdleLen()).To(BeNumerically("<=", 10))
+		Expect(pool.Len()).To(Equal(pool.IdleLen()))
 	})
 
 	It("removes broken connections", func() {
-		cn, _, err := client.Pool().Get()
+		cn, err := client.Pool().Get()
 		Expect(err).NotTo(HaveOccurred())
 		cn.SetNetConn(&badConn{})
-		Expect(client.Pool().Put(cn)).NotTo(HaveOccurred())
+		client.Pool().Put(cn)
 
 		err = client.Ping().Err()
 		Expect(err).To(MatchError("bad connection"))
@@ -92,7 +92,7 @@ var _ = Describe("pool", func() {
 
 		pool := client.Pool()
 		Expect(pool.Len()).To(Equal(1))
-		Expect(pool.FreeLen()).To(Equal(1))
+		Expect(pool.IdleLen()).To(Equal(1))
 
 		stats := pool.Stats()
 		Expect(stats.Hits).To(Equal(uint32(2)))
@@ -109,7 +109,7 @@ var _ = Describe("pool", func() {
 
 		pool := client.Pool()
 		Expect(pool.Len()).To(Equal(1))
-		Expect(pool.FreeLen()).To(Equal(1))
+		Expect(pool.IdleLen()).To(Equal(1))
 
 		stats := pool.Stats()
 		Expect(stats.Hits).To(Equal(uint32(100)))
@@ -125,6 +125,7 @@ var _ = Describe("pool", func() {
 			Timeouts:   0,
 			TotalConns: 1,
 			FreeConns:  1,
+			IdleConns:  1,
 			StaleConns: 0,
 		}))
 

redis.go

@@ -60,29 +60,30 @@ func (c *baseClient) newConn() (*pool.Conn, error) {
 	return cn, nil
 }
 
-func (c *baseClient) getConn() (*pool.Conn, bool, error) {
-	cn, isNew, err := c.connPool.Get()
+func (c *baseClient) getConn() (*pool.Conn, error) {
+	cn, err := c.connPool.Get()
 	if err != nil {
-		return nil, false, err
+		return nil, err
 	}
 
 	if !cn.Inited {
-		if err := c.initConn(cn); err != nil {
-			_ = c.connPool.Remove(cn)
-			return nil, false, err
+		err := c.initConn(cn)
+		if err != nil {
+			c.connPool.Remove(cn)
+			return nil, err
 		}
 	}
 
-	return cn, isNew, nil
+	return cn, nil
 }
 
 func (c *baseClient) releaseConn(cn *pool.Conn, err error) bool {
 	if internal.IsBadConn(err, false) {
-		_ = c.connPool.Remove(cn)
+		c.connPool.Remove(cn)
 		return false
 	}
 
-	_ = c.connPool.Put(cn)
+	c.connPool.Put(cn)
 	return true
 }
 
@@ -137,7 +138,7 @@ func (c *baseClient) defaultProcess(cmd Cmder) error {
 			time.Sleep(c.retryBackoff(attempt))
 		}
 
-		cn, _, err := c.getConn()
+		cn, err := c.getConn()
 		if err != nil {
 			cmd.setErr(err)
 			if internal.IsRetryableError(err, true) {
@@ -225,7 +226,7 @@ func (c *baseClient) generalProcessPipeline(cmds []Cmder, p pipelineProcessor) e
 			time.Sleep(c.retryBackoff(attempt))
 		}
 
-		cn, _, err := c.getConn()
+		cn, err := c.getConn()
 		if err != nil {
 			setCmdsErr(cmds, err)
 			return err
@@ -234,10 +235,10 @@ func (c *baseClient) generalProcessPipeline(cmds []Cmder, p pipelineProcessor) e
 		canRetry, err := p(cn, cmds)
 
 		if err == nil || internal.IsRedisError(err) {
-			_ = c.connPool.Put(cn)
+			c.connPool.Put(cn)
 			break
 		}
-		_ = c.connPool.Remove(cn)
+		c.connPool.Remove(cn)
 
 		if !canRetry || !internal.IsRetryableError(err, true) {
 			break

redis_test.go

@@ -145,12 +145,11 @@ var _ = Describe("Client", func() {
 		})
 
 		// Put bad connection in the pool.
-		cn, _, err := client.Pool().Get()
+		cn, err := client.Pool().Get()
 		Expect(err).NotTo(HaveOccurred())
 
 		cn.SetNetConn(&badConn{})
-		err = client.Pool().Put(cn)
-		Expect(err).NotTo(HaveOccurred())
+		client.Pool().Put(cn)
 
 		err = client.Ping().Err()
 		Expect(err).NotTo(HaveOccurred())
@@ -184,19 +183,18 @@ var _ = Describe("Client", func() {
 	})
 
 	It("should update conn.UsedAt on read/write", func() {
-		cn, _, err := client.Pool().Get()
+		cn, err := client.Pool().Get()
 		Expect(err).NotTo(HaveOccurred())
 		Expect(cn.UsedAt).NotTo(BeZero())
 		createdAt := cn.UsedAt()
 
-		err = client.Pool().Put(cn)
-		Expect(err).NotTo(HaveOccurred())
+		client.Pool().Put(cn)
 		Expect(cn.UsedAt().Equal(createdAt)).To(BeTrue())
 
 		err = client.Ping().Err()
 		Expect(err).NotTo(HaveOccurred())
 
-		cn, _, err = client.Pool().Get()
+		cn, err = client.Pool().Get()
 		Expect(err).NotTo(HaveOccurred())
 		Expect(cn).NotTo(BeNil())
 		Expect(cn.UsedAt().After(createdAt)).To(BeTrue())

ring.go

@@ -525,7 +525,7 @@ func (c *Ring) defaultProcessPipeline(cmds []Cmder) error {
 				continue
 			}
 
-			cn, _, err := shard.Client.getConn()
+			cn, err := shard.Client.getConn()
 			if err != nil {
 				setCmdsErr(cmds, err)
 				continue
@@ -533,10 +533,10 @@ func (c *Ring) defaultProcessPipeline(cmds []Cmder) error {
 
 			canRetry, err := shard.Client.pipelineProcessCmds(cn, cmds)
 			if err == nil || internal.IsRedisError(err) {
-				_ = shard.Client.connPool.Put(cn)
+				shard.Client.connPool.Put(cn)
 				continue
 			}
-			_ = shard.Client.connPool.Remove(cn)
+			shard.Client.connPool.Remove(cn)
 
 			if canRetry && internal.IsRetryableError(err, true) {
 				if failedCmdsMap == nil {

tx_test.go

@@ -124,12 +124,11 @@ var _ = Describe("Tx", func() {
 
 	It("should recover from bad connection", func() {
 		// Put bad connection in the pool.
-		cn, _, err := client.Pool().Get()
+		cn, err := client.Pool().Get()
 		Expect(err).NotTo(HaveOccurred())
 
 		cn.SetNetConn(&badConn{})
-		err = client.Pool().Put(cn)
-		Expect(err).NotTo(HaveOccurred())
+		client.Pool().Put(cn)
 
 		do := func() error {
 			err := client.Watch(func(tx *redis.Tx) error {