diff --git a/lib_fiber/c/src/common/gettimeofday.c b/lib_fiber/c/src/common/gettimeofday.c
index decf40c5e..e1bdd49fe 100644
--- a/lib_fiber/c/src/common/gettimeofday.c
+++ b/lib_fiber/c/src/common/gettimeofday.c
@@ -143,6 +143,26 @@ int gettimeofday(struct timeval *tv, struct timezone *tz)
 
 #elif defined(USE_FAST_TIME)
 
+#include "fiber.h"
+
+typedef int (*gettimeofday_fn)(struct timeval *, struct timezone *);
+static gettimeofday_fn __gettimeofday = NULL;
+
+static void hook_api(void)
+{
+	__gettimeofday = (gettimeofday_fn) dlsym(RTLD_NEXT, "gettimeofday");
+	assert(__gettimeofday);
+}
+
+static pthread_once_t __once_control = PTHREAD_ONCE_INIT;
+
+static void hook_init(void)
+{
+	if (pthread_once(&__once_control, hook_api) != 0) {
+		abort();
+	}
+}
+
 static inline unsigned long long rte_rdtsc(void)
 {
 	union {
@@ -168,12 +188,13 @@ static void set_time_metric(void)
 	unsigned long long now, startup, end;
 	unsigned long long begin = rte_rdtsc();
 
-#define MSEC_ONE 1000
+#define MSEC_ONE 	1000
+#define METRIC		50
 
-	usleep(MSEC_ONE);
+	usleep(MSEC_ONE * METRIC);
 
 	end           = rte_rdtsc();
-	__one_msec    = end - begin;
+	__one_msec    = (end - begin) / METRIC;
 	__one_sec     = __one_msec * 1000;
 
 	startup       = rte_rdtsc();
@@ -201,6 +222,13 @@ int acl_fiber_gettimeofday(struct timeval *tv, struct timezone *tz fiber_unused)
 
 int gettimeofday(struct timeval *tv, struct timezone *tz)
 {
+	if (!var_hook_sys_api) {
+		if (__gettimeofday == NULL) {
+			hook_init();
+		}
+		return __gettimeofday(tv, tz);
+	}
+
 	return acl_fiber_gettimeofday(tv, tz);
 }
 
diff --git a/lib_fiber/c/src/fiber.h b/lib_fiber/c/src/fiber.h
index 9261c0f55..9d4ddc7ac 100644
--- a/lib_fiber/c/src/fiber.h
+++ b/lib_fiber/c/src/fiber.h
@@ -1,6 +1,7 @@
 #ifndef FIBER_INCLUDE_H
 #define FIBER_INCLUDE_H
 
+#include "common/ring.h"
 #include "event.h"
 
 #ifdef ACL_ARM_LINUX
diff --git a/lib_fiber/c/src/hook/io.c b/lib_fiber/c/src/hook/io.c
index 136651d2f..18b3284b3 100644
--- a/lib_fiber/c/src/hook/io.c
+++ b/lib_fiber/c/src/hook/io.c
@@ -222,13 +222,14 @@ static void hook_init(void)
 #ifdef SYS_UNIX
 unsigned int sleep(unsigned int seconds)
 {
-	if (!var_hook_sys_api) {
+	if (var_hook_sys_api) {
 #ifndef USE_SYSCALL
 		if (__sys_sleep == NULL) {
 			hook_init();
 		}
 #endif
 
+		printf("use system gettimeofday\r\n");
 		return __sys_sleep(seconds);
 	}
 
diff --git a/lib_fiber/changes.txt b/lib_fiber/changes.txt
index 71c734e7e..b6bc28bbb 100644
--- a/lib_fiber/changes.txt
+++ b/lib_fiber/changes.txt
@@ -1,4 +1,7 @@
 
+110) 2019.8.6
+110.1) bugfix: gettimeofday 内部在进行时间校准时休眠 50 毫秒，之前是休眠 1 毫秒造成较大误差
+
 109) 2019.7.31
 109.1) performance: 因为 ring.h 中的方法被调用次数比较频繁，所以将其中代码实现
 放在头文件中，成为内联函数或宏定义