diff --git a/src/sf_connection_manager.c b/src/sf_connection_manager.c
index 57be9c7..62231d3 100644
--- a/src/sf_connection_manager.c
+++ b/src/sf_connection_manager.c
@@ -522,6 +522,11 @@ int sf_connection_manager_init_ex(SFConnectionManager *cm,
         const bool bg_thread_enabled)
 {
     const int socket_domain = AF_INET;
+    struct {
+        ConnectionExtraParams holder;
+        ConnectionExtraParams *ptr;
+    } extra_params;
+    FCServerGroupInfo *server_group;
     int htable_init_capacity;
     int result;
 
@@ -529,11 +534,27 @@ int sf_connection_manager_init_ex(SFConnectionManager *cm,
     if (htable_init_capacity < 256) {
         htable_init_capacity = 256;
     }
+
+    if ((server_group=fc_server_get_group_by_index(server_cfg,
+                    server_group_index)) == NULL)
+    {
+        return ENOENT;
+    }
+
+    if (server_group->comm_type == fc_comm_type_sock) {
+        extra_params.ptr = NULL;
+    } else {
+        //TODO: fix me!!!
+        extra_params.holder.buffer_size = 256 * 1024;
+        extra_params.holder.pd = NULL;
+        extra_params.ptr = &extra_params.holder;
+    }
     if ((result=conn_pool_init_ex1(&cm->cpool, common_cfg->connect_timeout,
                     max_count_per_entry, max_idle_time, socket_domain,
                     htable_init_capacity, connect_done_callback, args,
                     sf_cm_validate_connection_callback, cm,
-                    sizeof(SFConnectionParameters))) != 0)
+                    sizeof(SFConnectionParameters),
+                    extra_params.ptr)) != 0)
     {
         return result;
     }
diff --git a/src/sf_global.c b/src/sf_global.c
index 9e57dfa..7d7a9ea 100644
--- a/src/sf_global.c
+++ b/src/sf_global.c
@@ -415,17 +415,19 @@ int sf_load_config_ex(const char *server_name, SFContextIniConfig *config,
 
 #define API_PREFIX_NAME  "fast_rdma_"
 
-#define LOAD_API(handler, fname) \
+#define LOAD_API_EX(handler, prefix, fname) \
     do { \
-        handler->fname = dlsym(dlhandle, API_PREFIX_NAME#fname); \
+        handler->fname = dlsym(dlhandle, API_PREFIX_NAME#prefix#fname); \
         if (handler->fname == NULL) {  \
             logError("file: "__FILE__", line: %d, "  \
                     "dlsym api %s fail, error info: %s", \
-                    __LINE__, API_PREFIX_NAME#fname, dlerror()); \
+                    __LINE__, API_PREFIX_NAME#prefix#fname, dlerror()); \
             return ENOENT; \
         } \
     } while (0)
 
+#define LOAD_API(handler, fname)  LOAD_API_EX(handler, "server_", fname)
+
 static int load_rdma_apis(SFNetworkHandler *handler)
 {
     const char *library = "libfastrdma.so";
@@ -442,11 +444,11 @@ static int load_rdma_apis(SFNetworkHandler *handler)
     LOAD_API(handler, get_connection_size);
     LOAD_API(handler, init_connection);
     LOAD_API(handler, alloc_pd);
-    LOAD_API(handler, create_server);
-    LOAD_API(handler, close_server);
+    LOAD_API_EX(handler, "", create_server);
+    LOAD_API_EX(handler, "", close_server);
     LOAD_API(handler, accept_connection);
-    LOAD_API(handler, async_connect_server);
-    LOAD_API(handler, connect_server_done);
+    LOAD_API_EX(handler, "", async_connect_server);
+    LOAD_API_EX(handler, "", connect_server_done);
     LOAD_API(handler, close_connection);
     LOAD_API(handler, send_data);
     LOAD_API(handler, recv_data);
diff --git a/src/sf_proto.c b/src/sf_proto.c
index c7e45b0..905507f 100644
--- a/src/sf_proto.c
+++ b/src/sf_proto.c
@@ -99,7 +99,7 @@ static inline int sf_recv_response_header(ConnectionInfo *conn,
     SFCommonProtoHeader header_proto;
 
     if ((result=tcprecvdata_nb(conn->sock, &header_proto,
-            sizeof(SFCommonProtoHeader), network_timeout)) != 0)
+                    sizeof(SFCommonProtoHeader), network_timeout)) != 0)
     {
         response->error.length = snprintf(response->error.message,
                 sizeof(response->error.message),
@@ -108,18 +108,7 @@ static inline int sf_recv_response_header(ConnectionInfo *conn,
         return result;
     }
 
-    if (!SF_PROTO_CHECK_MAGIC(header_proto.magic)) {
-        response->error.length = snprintf(response->error.message,
-                sizeof(response->error.message),
-                "magic "SF_PROTO_MAGIC_FORMAT" is invalid, "
-                "expect: "SF_PROTO_MAGIC_FORMAT,
-                SF_PROTO_MAGIC_PARAMS(header_proto.magic),
-                SF_PROTO_MAGIC_EXPECT_PARAMS);
-        return EINVAL;
-    }
-
-    sf_proto_extract_header(&header_proto, &response->header);
-    return 0;
+    return sf_proto_parse_header(&header_proto, response);
 }
 
 int sf_send_and_recv_response_header(ConnectionInfo *conn, char *data,
diff --git a/src/sf_proto.h b/src/sf_proto.h
index 07e6037..5871f9f 100644
--- a/src/sf_proto.h
+++ b/src/sf_proto.h
@@ -535,16 +535,27 @@ int sf_send_and_recv_vary_response(ConnectionInfo *conn,
         const int network_timeout, const unsigned char expect_cmd,
         SFProtoRecvBuffer *buffer, const int min_body_len);
 
-static inline void sf_proto_extract_header(const SFCommonProtoHeader
-        *header_proto, SFHeaderInfo *header_info)
+static inline int sf_proto_parse_header(const SFCommonProtoHeader
+        *header_proto, SFResponseInfo *response)
 {
-    header_info->cmd = header_proto->cmd;
-    header_info->body_len = buff2int(header_proto->body_len);
-    header_info->flags = buff2short(header_proto->flags);
-    header_info->status = buff2short(header_proto->status);
-    if (header_info->status > 255) {
-        header_info->status = sf_localize_errno(header_info->status);
+    if (!SF_PROTO_CHECK_MAGIC(header_proto->magic)) {
+        response->error.length = snprintf(response->error.message,
+                sizeof(response->error.message),
+                "magic "SF_PROTO_MAGIC_FORMAT" is invalid, "
+                "expect: "SF_PROTO_MAGIC_FORMAT,
+                SF_PROTO_MAGIC_PARAMS(header_proto->magic),
+                SF_PROTO_MAGIC_EXPECT_PARAMS);
+        return EINVAL;
     }
+
+    response->header.cmd = header_proto->cmd;
+    response->header.body_len = buff2int(header_proto->body_len);
+    response->header.flags = buff2short(header_proto->flags);
+    response->header.status = buff2short(header_proto->status);
+    if (response->header.status > 255) {
+        response->header.status = sf_localize_errno(response->header.status);
+    }
+    return 0;
 }
 
 static inline void sf_proto_pack_limit(const SFListLimitInfo