diff --git a/trunk/src/app/srs_app_bandwidth.cpp b/trunk/src/app/srs_app_bandwidth.cpp
index c7963fe9b..3981a6ccc 100644
--- a/trunk/src/app/srs_app_bandwidth.cpp
+++ b/trunk/src/app/srs_app_bandwidth.cpp
@@ -260,7 +260,7 @@ srs_error_t SrsBandwidth::play_checking(SrsBandwidthSample* sample, SrsKbpsLimit
     
     int data_count = 1;
     srs_utime_t starttime = srs_update_system_time();
-    while (srsu2ms(srs_get_system_time() - starttime) < sample->duration_ms) {
+    while (int64_t(srsu2ms(srs_get_system_time() - starttime)) < sample->duration_ms) {
         srs_usleep(sample->interval_ms * SRS_UTIME_MILLISECONDS);
         
         // TODO: FIXME: use shared ptr message.
@@ -342,7 +342,7 @@ srs_error_t SrsBandwidth::publish_checking(SrsBandwidthSample* sample, SrsKbpsLi
     
     // recv publish msgs until @duration_ms ms
     srs_utime_t starttime = srs_update_system_time();
-    while (srsu2ms(srs_get_system_time() - starttime) < sample->duration_ms) {
+    while (int64_t(srsu2ms(srs_get_system_time() - starttime)) < sample->duration_ms) {
         SrsCommonMessage* msg = NULL;
         SrsBandwidthPacket* pkt = NULL;
         if ((err = _rtmp->expect_message<SrsBandwidthPacket>(&msg, &pkt)) != srs_success) {
diff --git a/trunk/src/kernel/srs_kernel_utility.cpp b/trunk/src/kernel/srs_kernel_utility.cpp
index 5dce8fd38..808370178 100644
--- a/trunk/src/kernel/srs_kernel_utility.cpp
+++ b/trunk/src/kernel/srs_kernel_utility.cpp
@@ -113,7 +113,7 @@ srs_utime_t srs_get_system_time()
     return _srs_system_time_us_cache;
 }
 
-srs_utime_t srs_get_system_startup_time_ms()
+srs_utime_t srs_get_system_startup_time()
 {
     if (_srs_system_time_startup_time <= 0) {
         srs_update_system_time();
diff --git a/trunk/src/kernel/srs_kernel_utility.hpp b/trunk/src/kernel/srs_kernel_utility.hpp
index f0ddf8662..2c4d31f16 100644
--- a/trunk/src/kernel/srs_kernel_utility.hpp
+++ b/trunk/src/kernel/srs_kernel_utility.hpp
@@ -44,7 +44,7 @@ extern srs_error_t srs_avc_nalu_read_bit(SrsBitBuffer* stream, int8_t& v);
 
 // get current system time in srs_utime_t, use cache to avoid performance problem
 extern srs_utime_t srs_get_system_time();
-extern srs_utime_t srs_get_system_startup_time_ms();
+extern srs_utime_t srs_get_system_startup_time();
 // the deamon st-thread will update it.
 extern srs_utime_t srs_update_system_time();
 
diff --git a/trunk/src/libs/srs_lib_bandwidth.cpp b/trunk/src/libs/srs_lib_bandwidth.cpp
index 3ef379d6b..757912e7e 100644
--- a/trunk/src/libs/srs_lib_bandwidth.cpp
+++ b/trunk/src/libs/srs_lib_bandwidth.cpp
@@ -312,7 +312,7 @@ int SrsBandwidthClient::publish_checking(int duration_ms, int play_kbps)
     
     int data_count = 1;
     int64_t starttime = srsu2ms(srs_update_system_time());
-    while ((srsu2ms(srs_get_system_time()) - starttime) < duration_ms) {
+    while (int64_t(srsu2ms(srs_get_system_time()) - starttime) < duration_ms) {
         // TODO: FIXME: use shared ptr message.
         SrsBandwidthPacket* pkt = SrsBandwidthPacket::create_publishing();