diff --git a/trunk/src/app/srs_app_config.hpp b/trunk/src/app/srs_app_config.hpp
index b2ffa60a5..2326e7a33 100644
--- a/trunk/src/app/srs_app_config.hpp
+++ b/trunk/src/app/srs_app_config.hpp
@@ -34,7 +34,6 @@
 #include <srs_app_reload.hpp>
 #include <srs_app_async_call.hpp>
 #include <srs_app_thread.hpp>
-#include <srs_core_time.hpp>
 
 class SrsRequest;
 class SrsFileWriter;
diff --git a/trunk/src/app/srs_app_conn.hpp b/trunk/src/app/srs_app_conn.hpp
index 2ae0b10a6..01e1e268d 100644
--- a/trunk/src/app/srs_app_conn.hpp
+++ b/trunk/src/app/srs_app_conn.hpp
@@ -33,7 +33,6 @@
 #include <srs_protocol_kbps.hpp>
 #include <srs_app_reload.hpp>
 #include <srs_service_conn.hpp>
-#include <srs_core_time.hpp>
 
 class SrsWallClock;
 
diff --git a/trunk/src/app/srs_app_dash.hpp b/trunk/src/app/srs_app_dash.hpp
index dd4467393..af32ee3b1 100644
--- a/trunk/src/app/srs_app_dash.hpp
+++ b/trunk/src/app/srs_app_dash.hpp
@@ -30,7 +30,6 @@
 #include <vector>
 
 #include <srs_app_fragment.hpp>
-#include <srs_core_time.hpp>
 
 class SrsRequest;
 class SrsOriginHub;
diff --git a/trunk/src/app/srs_app_hls.hpp b/trunk/src/app/srs_app_hls.hpp
index 0abb0a2dc..1a340b16b 100644
--- a/trunk/src/app/srs_app_hls.hpp
+++ b/trunk/src/app/srs_app_hls.hpp
@@ -33,7 +33,6 @@
 #include <srs_kernel_file.hpp>
 #include <srs_app_async_call.hpp>
 #include <srs_app_fragment.hpp>
-#include <srs_core_time.hpp>
 
 class SrsFormat;
 class SrsSharedPtrMessage;
diff --git a/trunk/src/app/srs_app_ingest.hpp b/trunk/src/app/srs_app_ingest.hpp
index f1ed8ab30..e8206a143 100644
--- a/trunk/src/app/srs_app_ingest.hpp
+++ b/trunk/src/app/srs_app_ingest.hpp
@@ -30,7 +30,6 @@
 
 #include <srs_app_thread.hpp>
 #include <srs_app_reload.hpp>
-#include <srs_core_time.hpp>
 
 class SrsFFMPEG;
 class SrsConfDirective;
diff --git a/trunk/src/app/srs_app_pithy_print.hpp b/trunk/src/app/srs_app_pithy_print.hpp
index cd4ace26b..ffbfc8b91 100644
--- a/trunk/src/app/srs_app_pithy_print.hpp
+++ b/trunk/src/app/srs_app_pithy_print.hpp
@@ -27,7 +27,6 @@
 #include <srs_core.hpp>
 
 #include <srs_app_reload.hpp>
-#include <srs_core_time.hpp>
 
 /**
  * the stage info to calc the age.
diff --git a/trunk/src/app/srs_app_source.hpp b/trunk/src/app/srs_app_source.hpp
index 6147f7da6..575508768 100644
--- a/trunk/src/app/srs_app_source.hpp
+++ b/trunk/src/app/srs_app_source.hpp
@@ -33,7 +33,6 @@
 #include <srs_app_st.hpp>
 #include <srs_app_reload.hpp>
 #include <srs_core_performance.hpp>
-#include <srs_core_time.hpp>
 
 class SrsFormat;
 class SrsRtmpFormat;
diff --git a/trunk/src/core/srs_core.hpp b/trunk/src/core/srs_core.hpp
index d1fdd16ae..63c470485 100644
--- a/trunk/src/core/srs_core.hpp
+++ b/trunk/src/core/srs_core.hpp
@@ -86,7 +86,10 @@
 #include <stddef.h>
 #include <sys/types.h>
 
-// important performance options.
+// Time defines.
+#include <srs_core_time.hpp>
+
+// Some important performance options.
 #include <srs_core_performance.hpp>
 
 // free the p and set to NULL.
diff --git a/trunk/src/core/srs_core_performance.cpp b/trunk/src/core/srs_core_performance.cpp
index 9e9f58799..28ebf57a1 100644
--- a/trunk/src/core/srs_core_performance.cpp
+++ b/trunk/src/core/srs_core_performance.cpp
@@ -21,5 +21,7 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
+#include <srs_core.hpp>
+
 #include <srs_core_performance.hpp>
 
diff --git a/trunk/src/core/srs_core_performance.hpp b/trunk/src/core/srs_core_performance.hpp
index efc743c9a..4c36b263a 100644
--- a/trunk/src/core/srs_core_performance.hpp
+++ b/trunk/src/core/srs_core_performance.hpp
@@ -24,9 +24,6 @@
 #ifndef SRS_CORE_PERFORMANCE_HPP
 #define SRS_CORE_PERFORMANCE_HPP
 
-#include <srs_core.hpp>
-#include <srs_core_time.hpp>
-
 /**
  * this file defines the perfromance options.
  */
diff --git a/trunk/src/core/srs_core_time.cpp b/trunk/src/core/srs_core_time.cpp
index 32ee3208c..749fb99c8 100644
--- a/trunk/src/core/srs_core_time.cpp
+++ b/trunk/src/core/srs_core_time.cpp
@@ -21,5 +21,7 @@
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
+#include <srs_core.hpp>
+
 #include <srs_core_time.hpp>
 
diff --git a/trunk/src/core/srs_core_time.hpp b/trunk/src/core/srs_core_time.hpp
index f9f7bdd5c..2713d41f8 100644
--- a/trunk/src/core/srs_core_time.hpp
+++ b/trunk/src/core/srs_core_time.hpp
@@ -24,8 +24,6 @@
 #ifndef SRS_CORE_TIME_HPP
 #define SRS_CORE_TIME_HPP
 
-#include <srs_core.hpp>
-
 // Time and duration unit, in us.
 typedef int64_t srs_utime_t;
 
diff --git a/trunk/src/kernel/srs_kernel_utility.hpp b/trunk/src/kernel/srs_kernel_utility.hpp
index 2c4d31f16..2d22391a2 100644
--- a/trunk/src/kernel/srs_kernel_utility.hpp
+++ b/trunk/src/kernel/srs_kernel_utility.hpp
@@ -29,7 +29,6 @@
 #include <string>
 #include <vector>
 
-#include <srs_core_time.hpp>
 
 class SrsBuffer;
 class SrsBitBuffer;
diff --git a/trunk/src/main/srs_main_ingest_hls.cpp b/trunk/src/main/srs_main_ingest_hls.cpp
index f8cc61795..ba405560e 100644
--- a/trunk/src/main/srs_main_ingest_hls.cpp
+++ b/trunk/src/main/srs_main_ingest_hls.cpp
@@ -46,7 +46,6 @@ using namespace std;
 #include <srs_service_http_conn.hpp>
 #include <srs_service_rtmp_conn.hpp>
 #include <srs_service_utility.hpp>
-#include <srs_core_time.hpp>
 
 // pre-declare
 srs_error_t proxy_hls2rtmp(std::string hls, std::string rtmp);
diff --git a/trunk/src/main/srs_main_server.cpp b/trunk/src/main/srs_main_server.cpp
index 87d3e8539..904f2cd73 100644
--- a/trunk/src/main/srs_main_server.cpp
+++ b/trunk/src/main/srs_main_server.cpp
@@ -48,7 +48,6 @@ using namespace std;
 #include <srs_core_performance.hpp>
 #include <srs_app_utility.hpp>
 #include <srs_core_autofree.hpp>
-#include <srs_core_time.hpp>
 
 // pre-declare
 srs_error_t run(SrsServer* svr);
diff --git a/trunk/src/service/srs_service_st.hpp b/trunk/src/service/srs_service_st.hpp
index 7119d3ace..14bd34d7e 100644
--- a/trunk/src/service/srs_service_st.hpp
+++ b/trunk/src/service/srs_service_st.hpp
@@ -25,7 +25,6 @@
 #define SRS_SERVICE_ST_HPP
 
 #include <srs_core.hpp>
-#include <srs_core_time.hpp>
 
 #include <string>