diff --git a/ants_benchmark_test.go b/ants_benchmark_test.go
index b88d8bf..f63d114 100644
--- a/ants_benchmark_test.go
+++ b/ants_benchmark_test.go
@@ -42,9 +42,9 @@ const (
 	YiB // 1208925819614629174706176
 )
 const (
-	RunTimes = 10000000
+	RunTimes = 1000000
 	Param    = 100
-	AntsSize = 1000
+	AntsSize = 50000
 	TestSize = 10000
 )
 
@@ -68,6 +68,7 @@ func demoPoolFunc(args interface{}) error {
 
 func BenchmarkGoroutineWithFunc(b *testing.B) {
 	var wg sync.WaitGroup
+
 	for i := 0; i < b.N; i++ {
 		for j := 0; j < RunTimes; j++ {
 			wg.Add(1)
@@ -96,7 +97,7 @@ func BenchmarkAntsPoolWithFunc(b *testing.B) {
 			p.Serve(Param)
 		}
 		wg.Wait()
-		b.Logf("running goroutines: %d", p.Running())
+		//b.Logf("running goroutines: %d", p.Running())
 	}
 }
 
@@ -111,7 +112,6 @@ func BenchmarkGoroutine(b *testing.B) {
 func BenchmarkAntsPool(b *testing.B) {
 	p, _ := ants.NewPoolWithFunc(AntsSize, demoPoolFunc)
 	defer p.Release()
-
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
 		for j := 0; j < RunTimes; j++ {
diff --git a/pool.go b/pool.go
index f3d931c..8fee19f 100644
--- a/pool.go
+++ b/pool.go
@@ -196,9 +196,17 @@ func (p *Pool) getWorker() *Worker {
 	}
 
 	if waiting {
-		p.cond.Wait()
-		l := len(p.workers) - 1
-		w = p.workers[l]
+		for{
+			p.cond.Wait()
+			l := len(p.workers) - 1
+			if l < 0{
+				continue
+			}
+			w = p.workers[l]
+			p.workers[l] = nil
+			p.workers = p.workers[:l]
+			break
+		}
 	} else if w == nil {
 		w = &Worker{
 			pool: p,
diff --git a/pool_func.go b/pool_func.go
index d1ed757..f0c75e5 100644
--- a/pool_func.go
+++ b/pool_func.go
@@ -198,9 +198,18 @@ func (p *PoolWithFunc) getWorker() *WorkerWithFunc {
 	}
 
 	if waiting {
-		p.cond.Wait()
-		l := len(p.workers) - 1
-		w = p.workers[l]
+		for{
+			p.cond.Wait()
+			l := len(p.workers) - 1
+			if l < 0{
+				continue
+			}
+			w = p.workers[l]
+			p.workers[l] = nil
+			p.workers = p.workers[:l]
+			break
+		}
+
 	} else if w == nil {
 		w = &WorkerWithFunc{
 			pool: p,