diff --git a/g/os/gfpool/gfpool.go b/g/os/gfpool/gfpool.go
index 2c47161f7..148babe75 100644
--- a/g/os/gfpool/gfpool.go
+++ b/g/os/gfpool/gfpool.go
@@ -89,6 +89,8 @@ func (p *Pool) File() (*File, error) {
             if _, err := f.Seek(0, 2); err != nil {
                 return nil, err
             }
+        } else {
+            f.Seek(0, 0)
         }
         if f.flag & os.O_CREATE > 0 {
             _, err := f.Stat()
@@ -103,10 +105,13 @@ func (p *Pool) File() (*File, error) {
             }
         }
         if f.flag & os.O_TRUNC > 0 {
-            if err := f.Truncate(0); err != nil {
-                return nil, err
+            if stat, err := f.Stat(); err == nil {
+                if stat.Size() > 0 {
+                    if err := f.Truncate(0); err != nil {
+                        return nil, err
+                    }
+                }
             }
-            f.Seek(0, 0)
         }
         return f, nil
     }
diff --git a/g/os/gfpool/gfpool_test.go b/g/os/gfpool/gfpool_test.go
new file mode 100644
index 000000000..beef6771f
--- /dev/null
+++ b/g/os/gfpool/gfpool_test.go
@@ -0,0 +1,21 @@
+package gfpool
+
+import (
+    "testing"
+    "os"
+)
+
+func Benchmark_os_Open_Close(b *testing.B) {
+    for i := 0; i < b.N; i++ {
+        f, _ := os.OpenFile("/tmp/bench-test", os.O_RDWR|os.O_CREATE|os.O_TRUNC|os.O_APPEND, 0766)
+        f.Close()
+    }
+}
+
+func Benchmark_gfpool_Open_Close(b *testing.B) {
+    for i := 0; i < b.N; i++ {
+        f, _ := Open("/tmp/bench-test", os.O_RDWR|os.O_CREATE|os.O_TRUNC|os.O_APPEND, 0766)
+        f.Close()
+    }
+}
+