diff --git a/.gitignore b/.gitignore
index 657581e..0830328 100644
--- a/.gitignore
+++ b/.gitignore
@@ -68,3 +68,5 @@ nutcracker
 
 Makefile
 Makefile.in
+
+/output
diff --git a/src/lua/pool.lua b/src/lua/pool.lua
index 3b60e71..e8b0682 100644
--- a/src/lua/pool.lua
+++ b/src/lua/pool.lua
@@ -14,6 +14,9 @@ ffi.cdef[[
       void ffi_server_table_delete(struct server_pool *pool, const char *name);
 
       rstatus_t ffi_stats_reset(struct server_pool *pool);
+
+      void ffi_slots_lock(struct server_pool *pool);
+      void ffi_slots_unlock(struct server_pool *pool);
 ]]
 
 local server = require("server")
@@ -42,7 +45,7 @@ function _M.fetch_server(self, config)
    else
       s = table.remove(self._se_pool, 1)
    end
-   
+
    return s
 end
 
@@ -59,7 +62,7 @@ function _M.fetch_replica_set(self)
    else
       rs = table.remove(self._rs_pool, 1)
    end
-   
+ 
    return rs
 end
 
@@ -167,9 +170,11 @@ function _M.build_replica_sets(self)
 end
 
 function _M.bind_slots(self)
+   C.ffi_slots_lock(__pool)
    for _,rs in ipairs(self.replica_sets) do
       rs:bind_slots()
    end
+   C.ffi_slots_unlock(__pool)
 end
 
 return _M
diff --git a/src/nc_script.c b/src/nc_script.c
index 5b2ea0a..c852719 100644
--- a/src/nc_script.c
+++ b/src/nc_script.c
@@ -194,8 +194,20 @@ ffi_server_disconnect(struct server *server)
 }
 
 void
-ffi_slots_set_replicaset(struct server_pool *pool, 
-                         struct replicaset *rs, 
+ffi_slots_lock(struct server_pool *pool) {
+    log_debug(LOG_VERB, "lock slots to update");
+    pthread_mutex_lock(&pool->slots_mutex);
+}
+
+void
+ffi_slots_unlock(struct server_pool *pool) {
+    log_debug(LOG_VERB, "unlock slots. update done");
+    pthread_mutex_unlock(&pool->slots_mutex);
+}
+
+void
+ffi_slots_set_replicaset(struct server_pool *pool,
+                         struct replicaset *rs,
                          int left, int right)
 {
     int i;
@@ -262,7 +274,28 @@ script_init(struct server_pool *pool)
     L = luaL_newstate();                        /* Create Lua state variable */
     pool->L = L;
     luaL_openlibs(L);                           /* Load Lua libraries */
-    if (luaL_loadfile(L, "lua/redis.lua")) {
+    #define MAX_PATH_LEN 1000
+    char path[MAX_PATH_LEN] = {'\0'};
+    char current[MAX_PATH_LEN] = {'\0'};
+    char *lua_name = "lua/redis.lua";
+
+    if (get_my_path(path, sizeof(path)) == NC_ERROR) {
+        log_error("get_my_path filed:%s", strerror(errno));
+        return NC_ERROR;
+    }
+
+    dirname(path);
+
+    log_debug(LOG_VERB, "lua script path is %s", path);
+
+    getcwd(current,sizeof(current));
+
+    if (chdir(path) < 0) {
+        log_error("chdir failed: %s", path);
+        return NC_ERROR;
+    }
+
+    if (luaL_loadfile(L, lua_name)) {
         log_debug(LOG_VERB, "init lua script failed - %s", lua_tostring(L, -1));
         return NC_ERROR;
     }
@@ -277,6 +310,10 @@ script_init(struct server_pool *pool)
     if (lua_pcall(L, 0, 0, 0) != 0) {
         log_error("call lua script failed - %s", lua_tostring(L, -1));
     }
+    if (chdir(current) < 0) {
+        log_error("chdir failed: %s", current);
+        return NC_ERROR;
+    }
 
     return NC_OK;
 }
diff --git a/src/nc_server.c b/src/nc_server.c
index 3967a86..4bbb378 100644
--- a/src/nc_server.c
+++ b/src/nc_server.c
@@ -852,6 +852,50 @@ server_pool_each_run(void *elem, void *data)
     return server_pool_run(elem);
 }
 
+static
+void *server_script_thread(void *elem) {
+    struct server_pool *sp = elem;
+    int64_t t_start, t_end;
+    sleep(2);
+    for(;;) {
+        char buf[1];
+        if (1 != read(sp->noti_fd[0], buf, sizeof(buf))) {
+            return NULL;
+        }
+        log_debug(LOG_VERB, "in server_scrip_thread: script_call");
+        t_start = nc_usec_now();
+        script_call(sp, sp->mbuf_thread->start, sp->mbuf_thread->last - sp->mbuf_thread->start, 
+                    "update_cluster_nodes");
+        t_end = nc_usec_now();
+        log_debug(LOG_VERB, "update slots done in %lldus",t_end - t_start);
+    }
+}
+
+/* init create the thread to run script and init a mutex*/
+static rstatus_t
+server_pool_each_script_thread(void *elem, void *data)
+{
+    struct server_pool *sp = elem;
+
+    if (pthread_mutex_init(&sp->slots_mutex, NULL) != 0) {
+        log_debug(LOG_WARN, "pthread_mutex_init failed");
+        return NC_ERROR;
+    }
+    /* create a pipe to notify */
+    if (pipe(sp->noti_fd) != 0) {
+        log_debug(LOG_WARN, "pipe failed");
+        return NC_ERROR;
+    }
+
+    /* start the thread*/
+    if (pthread_create(&sp->scri_thread, NULL, server_script_thread, (void *)sp)) {
+        log_debug(LOG_WARN, "pthread create failed");
+        return NC_ERROR;
+    }
+
+    return NC_OK;
+}
+
 static rstatus_t
 server_pool_each_set_table(void *elem, void *data)
 {
@@ -903,6 +947,12 @@ server_pool_init(struct array *server_pool, struct array *conf_pool,
         return status;
     }
 
+    /* init slots mutex */
+    status = array_each(server_pool, server_pool_each_script_thread, ctx);
+    if (status != NC_OK) {
+        return status;
+    }
+
     /* set tick callback */
     status = array_each(server_pool, server_pool_each_set_tick_callback, ctx);
     if (status != NC_OK) {
@@ -966,13 +1016,13 @@ server_pool_each_tick(void *elem, void *data)
     struct server_pool *pool = elem;
 
     pool->pool_tick(pool);
-    
+
     /* always returns NC_OK */
     return NC_OK;
 }
 
-void 
-server_pool_tick(struct context *ctx) 
+void
+server_pool_tick(struct context *ctx)
 {
     struct array *pools;
 
diff --git a/src/nc_server.h b/src/nc_server.h
index 0997aac..03a310e 100644
--- a/src/nc_server.h
+++ b/src/nc_server.h
@@ -143,6 +143,10 @@ struct server_pool {
     struct string      zone;                 /* avaliablity zone */
     struct hash_table  *server_table;        /* address(ip:port) to server map */
     struct replicaset  *slots[REDIS_CLUSTER_SLOTS];
+    pthread_mutex_t    slots_mutex;          /* mutex to access the slot */
+    pthread_t          scri_thread;
+    int                noti_fd[2];           /* pipe fd to notify thread */
+    struct mbuf        *mbuf_thread;         /* set the value before call the script thread */
     lua_State *L;
 };
 
diff --git a/src/nc_util.c b/src/nc_util.c
index a300faf..ad5827e 100644
--- a/src/nc_util.c
+++ b/src/nc_util.c
@@ -634,3 +634,11 @@ nc_unresolve_desc(int sd)
 
     return nc_unresolve_addr(addr, addrlen);
 }
+
+int
+get_my_path(char *buf, int len) {
+    if (buf == NULL) {
+        return NC_ERROR;
+    }
+    return readlink("/proc/self/exe", buf, len);
+}
diff --git a/src/nc_util.h b/src/nc_util.h
index f718532..80d5a4d 100644
--- a/src/nc_util.h
+++ b/src/nc_util.h
@@ -212,4 +212,7 @@ char *nc_unresolve_addr(struct sockaddr *addr, socklen_t addrlen);
 char *nc_unresolve_peer_desc(int sd);
 char *nc_unresolve_desc(int sd);
 
+/* return binary path in buf and len */
+int get_my_path(char *buf, int len);
+
 #endif
diff --git a/src/proto/nc_redis.c b/src/proto/nc_redis.c
index b2a1a34..57546ee 100644
--- a/src/proto/nc_redis.c
+++ b/src/proto/nc_redis.c
@@ -2789,15 +2789,20 @@ redis_routing(struct context *ctx, struct server_pool *pool,
         struct server *server = NULL;
 
         idx = server_pool_hash(pool, key, keylen) % REDIS_CLUSTER_SLOTS;
-        
+
         if (msg->type > MSG_REQ_REDIS_WRITECMD_START) {
+            pthread_mutex_lock(&pool->slots_mutex);
             server = pool->slots[idx]->master;
+            pthread_mutex_unlock(&pool->slots_mutex);
         } else {
             for (i = 0; i < NC_MAXTAGNUM; i++) {
                 uint32_t n;
                 struct array *slaves;
 
+                pthread_mutex_lock(&pool->slots_mutex);
                 slaves = &pool->slots[idx]->tagged_servers[i];
+                pthread_mutex_unlock(&pool->slots_mutex);
+
                 if (array_n(slaves) == 0) {
                     continue;
                 }
@@ -2949,7 +2954,9 @@ redis_pre_rsp_forward(struct context *ctx, struct conn * s_conn, struct msg *msg
             keylen = (uint32_t)(kpos->end - kpos->start);
             idx = pool->key_hash((char*)key, keylen) % REDIS_CLUSTER_SLOTS;
             if (msg->integer != idx) {
+                pthread_mutex_lock(&pool->slots_mutex);
                 pool->slots[idx] = pool->slots[msg->integer];
+                pthread_mutex_unlock(&pool->slots_mutex);
             }
         }
 
@@ -2958,7 +2965,7 @@ redis_pre_rsp_forward(struct context *ctx, struct conn * s_conn, struct msg *msg
 
 ferror:
         log_debug(LOG_WARN, "server: failed to redirect message");
-        
+
         msg_put(pmsg);
         msg_put(msg);
         return NC_ERROR;
@@ -2969,16 +2976,15 @@ redis_pre_rsp_forward(struct context *ctx, struct conn * s_conn, struct msg *msg
         int64_t t_start, t_end;
         struct mbuf *mbuf;
 
-        server = s_conn->owner;
-        pool = server->owner;
-
         /* FIXME: check length */
         mbuf = STAILQ_FIRST(&msg->mhdr);
-        t_start = nc_usec_now();
-        script_call(pool, mbuf->start, mbuf->last - mbuf->start, "update_cluster_nodes");
-        t_end = nc_usec_now();
-        log_debug(LOG_VERB, "update slots done in %lldus", t_end - t_start);
+
+        pool->mbuf_thread = mbuf;
         req_put(pmsg);
+
+        if (write(pool->noti_fd[1], "1", 1) != 1) {
+            log_debug(LOG_WARN, "write to pipe failed");
+        }
         return NC_ERROR;
     }