diff --git a/trunk/src/app/srs_app_edge.cpp b/trunk/src/app/srs_app_edge.cpp
index d91e27700..d0dca20ec 100644
--- a/trunk/src/app/srs_app_edge.cpp
+++ b/trunk/src/app/srs_app_edge.cpp
@@ -474,7 +474,7 @@ int SrsEdgeForwarder::cycle()
     
     SrsPithyPrint pithy_print(SRS_CONSTS_STAGE_EDGE);
     
-    SrsSharedPtrMessageArray msgs(SYS_MAX_EDGE_SEND_MSGS);
+    SrsMessageArray msgs(SYS_MAX_EDGE_SEND_MSGS);
 
     while (pthread->can_loop()) {
         if (send_error_code != ERROR_SUCCESS) {
@@ -526,7 +526,7 @@ int SrsEdgeForwarder::cycle()
         // @remark, becareful, all msgs must be free explicitly,
         //      free by send_and_free_message or srs_freep.
         for (int i = 0; i < count; i++) {
-            SrsSharedPtrMessage* msg = msgs.msgs[i];
+            SrsMessage* msg = msgs.msgs[i];
             
             srs_assert(msg);
             msgs.msgs[i] = NULL;
diff --git a/trunk/src/app/srs_app_forward.cpp b/trunk/src/app/srs_app_forward.cpp
index 78360d6de..831d065d5 100644
--- a/trunk/src/app/srs_app_forward.cpp
+++ b/trunk/src/app/srs_app_forward.cpp
@@ -381,7 +381,7 @@ int SrsForwarder::forward()
     
     SrsPithyPrint pithy_print(SRS_CONSTS_STAGE_FORWARDER);
 
-    SrsSharedPtrMessageArray msgs(SYS_MAX_FORWARD_SEND_MSGS);
+    SrsMessageArray msgs(SYS_MAX_FORWARD_SEND_MSGS);
     
     // update sequence header
     // TODO: FIXME: maybe need to zero the sequence header timestamp.
@@ -442,7 +442,7 @@ int SrsForwarder::forward()
         // @remark, becareful, all msgs must be free explicitly,
         //      free by send_and_free_message or srs_freep.
         for (int i = 0; i < count; i++) {
-            SrsSharedPtrMessage* msg = msgs.msgs[i];
+            SrsMessage* msg = msgs.msgs[i];
             
             srs_assert(msg);
             msgs.msgs[i] = NULL;
diff --git a/trunk/src/app/srs_app_rtmp_conn.cpp b/trunk/src/app/srs_app_rtmp_conn.cpp
index 186760361..8fcc3625c 100644
--- a/trunk/src/app/srs_app_rtmp_conn.cpp
+++ b/trunk/src/app/srs_app_rtmp_conn.cpp
@@ -517,7 +517,7 @@ int SrsRtmpConn::playing(SrsSource* source)
     
     // initialize other components
     SrsPithyPrint pithy_print(SRS_CONSTS_STAGE_PLAY_USER);
-    SrsSharedPtrMessageArray msgs(SYS_CONSTS_MAX_PLAY_SEND_MSGS);
+    SrsMessageArray msgs(SYS_CONSTS_MAX_PLAY_SEND_MSGS);
     bool user_specified_duration_to_stop = (req->duration > 0);
     int64_t starttime = -1;
     
@@ -574,7 +574,7 @@ int SrsRtmpConn::playing(SrsSource* source)
         // we start to collect the durations for each message.
         if (user_specified_duration_to_stop) {
             for (int i = 0; i < count; i++) {
-                SrsSharedPtrMessage* msg = msgs.msgs[i];
+                SrsMessage* msg = msgs.msgs[i];
                 
                 // foreach msg, collect the duration.
                 // @remark: never use msg when sent it, for the protocol sdk will free it.
diff --git a/trunk/src/app/srs_app_source.cpp b/trunk/src/app/srs_app_source.cpp
index f25e64e3e..4f578f075 100644
--- a/trunk/src/app/srs_app_source.cpp
+++ b/trunk/src/app/srs_app_source.cpp
@@ -192,7 +192,7 @@ int SrsMessageQueue::enqueue(SrsSharedPtrMessage* msg)
     return ret;
 }
 
-int SrsMessageQueue::dump_packets(int max_count, SrsSharedPtrMessage** pmsgs, int& count)
+int SrsMessageQueue::dump_packets(int max_count, SrsMessage** pmsgs, int& count)
 {
     int ret = ERROR_SUCCESS;
     
@@ -207,7 +207,7 @@ int SrsMessageQueue::dump_packets(int max_count, SrsSharedPtrMessage** pmsgs, in
         pmsgs[i] = msgs[i];
     }
     
-    SrsSharedPtrMessage* last = msgs[count - 1];
+    SrsMessage* last = msgs[count - 1];
     av_start_time = last->header.timestamp;
     
     if (count == (int)msgs.size()) {
@@ -332,7 +332,7 @@ int SrsConsumer::enqueue(SrsSharedPtrMessage* msg, bool atc, int tba, int tbv, S
     return ret;
 }
 
-int SrsConsumer::dump_packets(int max_count, SrsSharedPtrMessage** pmsgs, int& count)
+int SrsConsumer::dump_packets(int max_count, SrsMessage** pmsgs, int& count)
 {
     srs_assert(max_count > 0);
     
diff --git a/trunk/src/app/srs_app_source.hpp b/trunk/src/app/srs_app_source.hpp
index 1759ebf7e..2ac9b7f9e 100644
--- a/trunk/src/app/srs_app_source.hpp
+++ b/trunk/src/app/srs_app_source.hpp
@@ -132,7 +132,7 @@ public:
     * @count the count in array, output param.
     * @max_count the max count to dequeue, must be positive.
     */
-    virtual int dump_packets(int max_count, SrsSharedPtrMessage** pmsgs, int& count);
+    virtual int dump_packets(int max_count, SrsMessage** pmsgs, int& count);
 private:
     /**
     * remove a gop from the front.
@@ -187,7 +187,7 @@ public:
     * @count the count in array, output param.
     * @max_count the max count to dequeue, must be positive.
     */
-    virtual int dump_packets(int max_count, SrsSharedPtrMessage** pmsgs, int& count);
+    virtual int dump_packets(int max_count, SrsMessage** pmsgs, int& count);
     /**
     * when client send the pause message.
     */
diff --git a/trunk/src/core/srs_core.hpp b/trunk/src/core/srs_core.hpp
index 5c2ebd320..b0d342283 100644
--- a/trunk/src/core/srs_core.hpp
+++ b/trunk/src/core/srs_core.hpp
@@ -31,7 +31,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 // current release version
 #define VERSION_MAJOR       2
 #define VERSION_MINOR       0
-#define VERSION_REVISION    16
+#define VERSION_REVISION    17
 // server info.
 #define RTMP_SIG_SRS_KEY "SRS"
 #define RTMP_SIG_SRS_ROLE "origin/edge server"
diff --git a/trunk/src/rtmp/srs_protocol_msg_array.cpp b/trunk/src/rtmp/srs_protocol_msg_array.cpp
index c936fdb2c..54c96e93d 100644
--- a/trunk/src/rtmp/srs_protocol_msg_array.cpp
+++ b/trunk/src/rtmp/srs_protocol_msg_array.cpp
@@ -25,11 +25,11 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_protocol_stack.hpp>
 
-SrsSharedPtrMessageArray::SrsSharedPtrMessageArray(int _size)
+SrsMessageArray::SrsMessageArray(int _size)
 {
     srs_assert(_size > 0);
     
-    msgs = new SrsSharedPtrMessage*[_size];
+    msgs = new SrsMessage*[_size];
     size = _size;
     
     // initialize
@@ -38,11 +38,11 @@ SrsSharedPtrMessageArray::SrsSharedPtrMessageArray(int _size)
     }
 }
 
-SrsSharedPtrMessageArray::~SrsSharedPtrMessageArray()
+SrsMessageArray::~SrsMessageArray()
 {
     // cleanup
     for (int i = 0; i < size; i++) {
-        SrsSharedPtrMessage* msg = msgs[i];
+        SrsMessage* msg = msgs[i];
         srs_freep(msg);
     }
     
diff --git a/trunk/src/rtmp/srs_protocol_msg_array.hpp b/trunk/src/rtmp/srs_protocol_msg_array.hpp
index 5d3bf894e..c3a570a73 100644
--- a/trunk/src/rtmp/srs_protocol_msg_array.hpp
+++ b/trunk/src/rtmp/srs_protocol_msg_array.hpp
@@ -30,7 +30,7 @@ CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 
 #include <srs_core.hpp>
 
-class SrsSharedPtrMessage;
+class SrsMessage;
 
 /**
 * the class to auto free the shared ptr message array.
@@ -39,7 +39,7 @@ class SrsSharedPtrMessage;
 * then send each message and set to NULL.
 * @remark: when error, the message array will free the msg not sent out.
 */
-class SrsSharedPtrMessageArray
+class SrsMessageArray
 {
 public:
     /**
@@ -47,17 +47,17 @@ public:
     * for instance, msg= msgs.msgs[i], msgs.msgs[i]=NULL, send(msg),
     * where send(msg) will always send and free it.
     */
-    SrsSharedPtrMessage** msgs;
+    SrsMessage** msgs;
     int size;
 public:
     /**
     * create msg array, initialize array to NULL ptrs.
     */
-    SrsSharedPtrMessageArray(int _size);
+    SrsMessageArray(int _size);
     /**
     * free the msgs not sent out(not NULL).
     */
-    virtual ~SrsSharedPtrMessageArray();
+    virtual ~SrsMessageArray();
 };
 
 #endif
diff --git a/trunk/src/rtmp/srs_protocol_rtmp.cpp b/trunk/src/rtmp/srs_protocol_rtmp.cpp
index 76a0b2cb1..27fae2a2f 100644
--- a/trunk/src/rtmp/srs_protocol_rtmp.cpp
+++ b/trunk/src/rtmp/srs_protocol_rtmp.cpp
@@ -771,7 +771,7 @@ int SrsRtmpServer::send_and_free_message(SrsMessage* msg, int stream_id)
     return protocol->send_and_free_message(msg, stream_id);
 }
 
-int SrsRtmpServer::send_and_free_messages(SrsSharedPtrMessage** msgs, int nb_msgs, int stream_id)
+int SrsRtmpServer::send_and_free_messages(SrsMessage** msgs, int nb_msgs, int stream_id)
 {
     return protocol->send_and_free_messages(msgs, nb_msgs, stream_id);
 }
diff --git a/trunk/src/rtmp/srs_protocol_rtmp.hpp b/trunk/src/rtmp/srs_protocol_rtmp.hpp
index 70fc8e8ca..ab7f43955 100644
--- a/trunk/src/rtmp/srs_protocol_rtmp.hpp
+++ b/trunk/src/rtmp/srs_protocol_rtmp.hpp
@@ -378,7 +378,7 @@ public:
     * @remark performance issue, to support 6k+ 250kbps client,
     *       @see https://github.com/winlinvip/simple-rtmp-server/issues/194
     */
-    virtual int send_and_free_messages(SrsSharedPtrMessage** msgs, int nb_msgs, int stream_id);
+    virtual int send_and_free_messages(SrsMessage** msgs, int nb_msgs, int stream_id);
     /**
     * send the RTMP packet and always free it.
     * user must never free or use the packet after this method,
diff --git a/trunk/src/rtmp/srs_protocol_stack.cpp b/trunk/src/rtmp/srs_protocol_stack.cpp
index 8f2bb11a2..4394254fa 100644
--- a/trunk/src/rtmp/srs_protocol_stack.cpp
+++ b/trunk/src/rtmp/srs_protocol_stack.cpp
@@ -413,7 +413,7 @@ SrsProtocol::SrsProtocol(ISrsProtocolReaderWriter* io)
     // each chunk consumers atleast 2 iovs
     srs_assert(nb_out_iovs >= 2);
     
-    warned_c0c3_caches = false;
+    warned_c0c3_cry = false;
 }
 
 SrsProtocol::~SrsProtocol()
@@ -547,65 +547,7 @@ int SrsProtocol::decode_message(SrsMessage* msg, SrsPacket** ppacket)
     return ret;
 }
 
-int SrsProtocol::do_send_message(SrsMessage* msg)
-{
-    int ret = ERROR_SUCCESS;
-    
-    // ignore empty message.
-    if (!msg->payload || msg->size <= 0) {
-        srs_info("ignore empty message.");
-        return ret;
-    }
-    
-    // we donot use the complex basic header,
-    // ensure the basic header is 1bytes.
-    if (msg->header.perfer_cid < 2) {
-        srs_warn("change the chunk_id=%d to default=%d", 
-            msg->header.perfer_cid, RTMP_CID_ProtocolControl);
-        msg->header.perfer_cid = RTMP_CID_ProtocolControl;
-    }
-
-    // p set to current write position,
-    // it's ok when payload is NULL and size is 0.
-    char* p = msg->payload;
-    char* pend = msg->payload + msg->size;
-    
-    // always write the header event payload is empty.
-    while (p < pend) {
-        // always has header
-        int nbh = 0;
-        char* header = NULL;
-        generate_chunk_header(out_c0c3_cache, &msg->header, p == msg->payload, &nbh, &header);
-        srs_assert(nbh > 0);
-        
-        // header iov
-        out_iov[0].iov_base = header;
-        out_iov[0].iov_len = nbh;
-        
-        // payload iov
-        int payload_size = pend - p;
-        if (payload_size > out_chunk_size) {
-            payload_size = out_chunk_size;
-        }
-        out_iov[1].iov_base = p;
-        out_iov[1].iov_len = payload_size;
-        
-        // send by writev
-        // sendout header and payload by writev.
-        // decrease the sys invoke count to get higher performance.
-        if ((ret = skt->writev(out_iov, 2, NULL)) != ERROR_SUCCESS) {
-            srs_error("send with writev failed. ret=%d", ret);
-            return ret;
-        }
-        
-        // consume sendout bytes.
-        p += payload_size;
-    }
-    
-    return ret;
-}
-
-int SrsProtocol::do_send_messages(SrsSharedPtrMessage** msgs, int nb_msgs)
+int SrsProtocol::do_send_messages(SrsMessage** msgs, int nb_msgs)
 {
     int ret = ERROR_SUCCESS;
     
@@ -686,10 +628,10 @@ int SrsProtocol::do_send_messages(SrsSharedPtrMessage** msgs, int nb_msgs)
             int c0c3_left = SRS_CONSTS_C0C3_HEADERS_MAX - c0c3_cache_index;
             if (c0c3_left < SRS_CONSTS_RTMP_MAX_FMT0_HEADER_SIZE) {
                 // only warn once for a connection.
-                if (!warned_c0c3_caches) {
+                if (!warned_c0c3_cry) {
                     srs_warn("c0c3 cache header too small, recoment to %d", 
                         SRS_CONSTS_C0C3_HEADERS_MAX + SRS_CONSTS_RTMP_MAX_FMT0_HEADER_SIZE);
-                    warned_c0c3_caches = true;
+                    warned_c0c3_cry = true;
                 }
                 
                 // when c0c3 cache dry,
@@ -977,21 +919,10 @@ int SrsProtocol::do_decode_message(SrsMessageHeader& header, SrsStream* stream,
 
 int SrsProtocol::send_and_free_message(SrsMessage* msg, int stream_id)
 {
-    // always not NULL msg.
-    srs_assert(msg);
-    
-    // update the stream id in header.
-    msg->header.stream_id = stream_id;
-    
-    // donot use the auto free to free the msg,
-    // for performance issue.
-    int ret = do_send_message(msg);
-    srs_freep(msg);
-    
-    return ret;
+    return send_and_free_messages(&msg, 1, stream_id);
 }
 
-int SrsProtocol::send_and_free_messages(SrsSharedPtrMessage** msgs, int nb_msgs, int stream_id)
+int SrsProtocol::send_and_free_messages(SrsMessage** msgs, int nb_msgs, int stream_id)
 {
     // always not NULL msg.
     srs_assert(msgs);
@@ -1052,7 +983,7 @@ int SrsProtocol::send_and_free_packet(SrsPacket* packet, int stream_id)
 
     // donot use the auto free to free the msg,
     // for performance issue.
-    ret = do_send_message(msg);
+    ret = do_send_messages(&msg, 1);
     if (ret == ERROR_SUCCESS) {
         ret = on_send_packet(msg, packet);
     }
diff --git a/trunk/src/rtmp/srs_protocol_stack.hpp b/trunk/src/rtmp/srs_protocol_stack.hpp
index 2f4914d9c..a3f05b327 100644
--- a/trunk/src/rtmp/srs_protocol_stack.hpp
+++ b/trunk/src/rtmp/srs_protocol_stack.hpp
@@ -211,25 +211,22 @@ private:
     AckWindowSize in_ack_size;
 // peer out
 private:
-    /**
-    * output header cache.
-    * used for type0, 11bytes(or 15bytes with extended timestamp) header.
-    * or for type3, 1bytes(or 5bytes with extended timestamp) header.
-    */
-    char out_c0c3_cache[SRS_CONSTS_RTMP_MAX_FMT0_HEADER_SIZE];
-    /**
-    * output iovec cache.
-    */
-    iovec out_iov[2];
     /**
     * cache for multiple messages send
     */
     iovec* out_iovs;
     int nb_out_iovs;
-    // the c0c3 cache cannot be realloc.
+    /**
+    * output header cache.
+    * used for type0, 11bytes(or 15bytes with extended timestamp) header.
+    * or for type3, 1bytes(or 5bytes with extended timestamp) header.
+    * the c0c3 caches must use unit SRS_CONSTS_RTMP_MAX_FMT0_HEADER_SIZE bytes.
+    * 
+    * @remark, the c0c3 cache cannot be realloc.
+    */
     char out_c0c3_caches[SRS_CONSTS_C0C3_HEADERS_MAX];
     // whether warned user to increase the c0c3 header cache.
-    bool warned_c0c3_caches;
+    bool warned_c0c3_cry;
     /**
     * output chunk size, default to 128, set by config.
     */
@@ -293,7 +290,7 @@ public:
     * @param nb_msgs, the size of msgs to send out.
     * @param stream_id, the stream id of packet to send over, 0 for control message.
     */
-    virtual int send_and_free_messages(SrsSharedPtrMessage** msgs, int nb_msgs, int stream_id);
+    virtual int send_and_free_messages(SrsMessage** msgs, int nb_msgs, int stream_id);
     /**
     * send the RTMP packet and always free it.
     * user must never free or use the packet after this method,
@@ -362,16 +359,11 @@ public:
         return ret;
     }
 private:
-    /**
-    * send out the message, donot free it, 
-    * the caller must free the param msg.
-    */
-    virtual int do_send_message(SrsMessage* msg);
     /**
     * send out the messages, donot free it, 
     * the caller must free the param msgs.
     */
-    virtual int do_send_messages(SrsSharedPtrMessage** msgs, int nb_msgs);
+    virtual int do_send_messages(SrsMessage** msgs, int nb_msgs);
     /**
     * generate the chunk header for msg.
     * @param mh, the header of msg to send.
diff --git a/trunk/src/utest/srs_utest_protocol.cpp b/trunk/src/utest/srs_utest_protocol.cpp
index 0c1bd47c8..c6aabc7a6 100644
--- a/trunk/src/utest/srs_utest_protocol.cpp
+++ b/trunk/src/utest/srs_utest_protocol.cpp
@@ -529,7 +529,7 @@ VOID TEST(ProtocolMsgArrayTest, MessageArray)
     EXPECT_EQ(0, msg.count());
     
     if (true) {
-        SrsSharedPtrMessageArray arr(3);
+        SrsMessageArray arr(3);
         
         arr.msgs[0] = msg.copy();
         EXPECT_EQ(1, msg.count());
@@ -543,7 +543,7 @@ VOID TEST(ProtocolMsgArrayTest, MessageArray)
     EXPECT_EQ(0, msg.count());
     
     if (true) {
-        SrsSharedPtrMessageArray arr(3);
+        SrsMessageArray arr(3);
         
         arr.msgs[0] = msg.copy();
         EXPECT_EQ(1, msg.count());