diff --git a/ants_test.go b/ants_test.go
index 83519e8..aff9053 100644
--- a/ants_test.go
+++ b/ants_test.go
@@ -130,42 +130,4 @@ func TestCodeCov(t *testing.T) {
 	p.ReSize(TestSize)
 	p.ReSize(AntsSize)
 	t.Logf("pool with func, after resize, capacity:%d, running:%d", p.Cap(), p.Running())
-}
-
-// func TestNoPool(t *testing.T) {
-// 	var wg sync.WaitGroup
-// 	for i := 0; i < n; i++ {
-// 		wg.Add(1)
-// 		go func() {
-// 			demoPoolFunc(n)
-// 			wg.Done()
-// 		}()
-// 	}
-
-// 	wg.Wait()
-// 	mem := runtime.MemStats{}
-// 	runtime.ReadMemStats(&mem)
-// 	t.Logf("memory usage:%d", mem.TotalAlloc/GiB)
-// }
-
-//func TestCustomPool(t *testing.T) {
-//	p, _ := ants.NewPool(30000)
-//	var wg sync.WaitGroup
-//	for i := 0; i < n; i++ {
-//		wg.Add(1)
-//		p.Submit(func() {
-//			demoFunc()
-//			//demoFunc()
-//			wg.Done()
-//		})
-//	}
-//	wg.Wait()
-//
-//	//t.Logf("pool capacity:%d", p.Cap())
-//	//t.Logf("free workers number:%d", p.Free())
-//
-//	t.Logf("running workers number:%d", p.Running())
-//	mem := runtime.MemStats{}
-//	runtime.ReadMemStats(&mem)
-//	t.Logf("memory usage:%d", mem.TotalAlloc/1024)
-//}
+}
\ No newline at end of file
diff --git a/pool.go b/pool.go
index 2479f3b..987ba4d 100644
--- a/pool.go
+++ b/pool.go
@@ -67,7 +67,7 @@ func (p *Pool) periodicallyPurge() {
 			p.lock.Unlock()
 			return
 		}
-		n := 0
+		n := -1
 		for i, w := range idleWorkers {
 			if currentTime.Sub(w.recycleTime) <= p.expiryDuration {
 				break
@@ -76,11 +76,12 @@ func (p *Pool) periodicallyPurge() {
 			w.task <- nil
 			idleWorkers[i] = nil
 		}
-		n++
-		if n >= len(idleWorkers) {
-			p.workers = idleWorkers[:0]
-		} else {
-			p.workers = idleWorkers[n:]
+		if n > -1 {
+			if n >= len(idleWorkers)-1 {
+				p.workers = idleWorkers[:0]
+			} else {
+				p.workers = idleWorkers[n+1:]
+			}
 		}
 		p.lock.Unlock()
 	}
diff --git a/pool_func.go b/pool_func.go
index 5a3617c..6051117 100644
--- a/pool_func.go
+++ b/pool_func.go
@@ -68,7 +68,7 @@ func (p *PoolWithFunc) periodicallyPurge() {
 			p.lock.Unlock()
 			return
 		}
-		n := 0
+		n := -1
 		for i, w := range idleWorkers {
 			if currentTime.Sub(w.recycleTime) <= p.expiryDuration {
 				break
@@ -77,11 +77,12 @@ func (p *PoolWithFunc) periodicallyPurge() {
 			w.args <- nil
 			idleWorkers[i] = nil
 		}
-		n++
-		if n >= len(idleWorkers) {
-			p.workers = idleWorkers[:0]
-		} else {
-			p.workers = idleWorkers[n:]
+		if n > -1 {
+			if n >= len(idleWorkers)-1 {
+				p.workers = idleWorkers[:0]
+			} else {
+				p.workers = idleWorkers[n+1:]
+			}
 		}
 		p.lock.Unlock()
 	}