diff -urN rt_v37/cg.py rt_v38/cg.py
--- rt_v37/cg.py	2018-05-12 21:24:49.000000000 +0900
+++ rt_v38/cg.py	2018-05-16 23:42:46.000000000 +0900
@@ -42,6 +42,8 @@
 	eye_f = way.liss_eye()
 	wh2eye = lstx.opt( [ ax.wh_map(w, h), fcx.new(dz), ax.zoom_z(-1), ax.rot_x(90) ] )
 
+	rt.del_cache()
+
 	n = cnt.n
 	while cnt.up():
 		i = cnt.cur()
@@ -61,7 +63,7 @@
 	img.cli_vwt.close()
 
 	fn = name + '.mp4' # !
-	if ut.get_size(fn) > 3*1024*1024:
+	if ut.exists(fn) and ut.get_size(fn) > 3*1024*1024:
 		img.video_to_d1v3M(fn)
 
 	if n > 1 and (w,h,cnt.fps) != (640,480,30):
diff -urN rt_v37/dat.c rt_v38/dat.c
--- rt_v37/dat.c	2018-05-09 21:31:17.000000000 +0900
+++ rt_v38/dat.c	2018-05-16 23:42:46.000000000 +0900
@@ -135,25 +135,31 @@
 	return bp;
 }
 
+static pthread_mutex_t lock_func = PTHREAD_MUTEX_INITIALIZER;
+
 struct data *
 data_get(void)
 {
+	pthread_mutex_lock(&lock_func);
 	if(data.lst == NULL){
 		char *b = get_prop("data", NULL);
 		unpack_data(b, &data);
 		free(b);
 	}
+	pthread_mutex_unlock(&lock_func);
 	return &data;
 }
 
 struct lights *
 lights_get(void)
 {
+	pthread_mutex_lock(&lock_func);
 	if(lights.lst == NULL){
 		char *b = get_prop("lights", NULL);
 		unpack_lights(b, &lights);
 		free(b);
 	}	
+	pthread_mutex_unlock(&lock_func);
 	return &lights;
 }
 
@@ -211,4 +217,17 @@
 	FREE_LST(*lights, "lights");
 }
 
+void
+free_all(void)
+{
+	pthread_mutex_lock(&lock_func);
+	if(data.lst){
+		free_data(&data);
+	}
+	if(lights.lst){
+		free_lights(&lights);
+	}
+	pthread_mutex_unlock(&lock_func);
+}
+
 /* EOF */
diff -urN rt_v37/dat.h rt_v38/dat.h
--- rt_v37/dat.h	2018-05-09 21:31:17.000000000 +0900
+++ rt_v38/dat.h	2018-05-16 23:42:46.000000000 +0900
@@ -68,6 +68,7 @@
 void free_data_one(struct data_one *d);
 void free_data(struct data *data);
 void free_lights(struct lights *lights);
+void free_all(void);
 
 /**/
 
diff -urN rt_v37/rt.c rt_v38/rt.c
--- rt_v37/rt.c	2018-05-12 12:52:49.000000000 +0900
+++ rt_v38/rt.c	2018-05-16 23:42:46.000000000 +0900
@@ -410,6 +410,19 @@
 	write_n(fd, &sz, sizeof(sz));
 }
 
+void
+srv_del_cache(int fd)
+{
+	int sz;
+
+	read_n(fd, &sz, sizeof(sz));
+
+	free_all(); /* dat.c */
+
+	sz = 0;
+	write_n(fd, &sz, sizeof(sz));
+}
+
 int
 main(int ac, char **av)
 {
@@ -418,12 +431,13 @@
 		srv_calc_diff,
 		srv_get_col,
 		srv_set_cols,
+		srv_del_cache,
 	};
 
 	if(arg_is(ac, av, 1, "boot")){
 		char *name = arg_s(ac, av, "name", "srv.rt");
 		int port = arg_i(ac, av, "port", -1);
-		int do_lock_func = 1;
+		int do_lock_func = 0;
 		if(port < 0){
 			char *buf = get_prop(name, NULL), *bp = buf;
 			bp = COPY_FROM_BP(bp, port);
diff -urN rt_v37/rt.py rt_v38/rt.py
--- rt_v37/rt.py	2018-05-12 10:29:09.000000000 +0900
+++ rt_v38/rt.py	2018-05-16 23:39:41.000000000 +0900
@@ -20,6 +20,7 @@
 lights_get = lambda : ut.dic_cache( srv_dic, 'lights', lambda : val.cli.get_prop('lights') )
 
 data_one_get = lambda idx: data_get()[idx]
+del_cache = lambda : srv_dic.clear()
 
 def map_col(idx, l_nv_g, rev, sec):
 	d = data_one_get(idx)
@@ -121,8 +122,6 @@
 	if idx < 0:
 		return []
 
-	#data = ut.dic_cache( srv_dic, 'data', lambda : val.cli.get_prop('data') )
-	#d = data[idx]
 	d = data_one_get(idx)
 	rtd = d.get('rtd', {})
 	crsp = l_nv_g.p
@@ -202,6 +201,7 @@
 	{ 'cmd': 'calc_diff', 'func': calc_diff, 'args': '(i4,xyz,xyz,f8)', 'rets': 'f8' },
 	{ 'cmd': 'get_col', 'func': get_col, 'args': '(line,f8,f8,i4)', 'rets': 'col' },
 	{ 'cmd': 'set_cols', 'func': set_cols, 'args':'(xyz,lx,f8,f8,i4,i4,i4,i4)' },
+	{ 'cmd': 'del_cache', 'func': del_cache },
 ]
 
 cli = sock.new_client('srv.rt', cmd_infs)
@@ -225,6 +225,10 @@
 
 clis = ut.map_lst( add_cli_info, zip(clis, rates) )
 
+def del_cache():
+	for cli in clis:
+		cli.del_cache()
+
 if __name__ == "__main__":
 	if ut.arg_is(1, 'boot'):
 		name = ut.arg_s('name', 'srv.rt')
diff -urN rt_v37/sock.c rt_v38/sock.c
--- rt_v37/sock.c	2018-05-12 01:58:09.000000000 +0900
+++ rt_v38/sock.c	2018-05-16 23:38:55.000000000 +0900
@@ -163,12 +163,38 @@
 	return n;
 }
 
+#define LOCK_FDS_N	64
+pthread_mutex_t lock_fds[ LOCK_FDS_N ];
+int lock_fds_inited = 0;
+
+static void
+lock_fd(int fd)
+{
+	if(!lock_fds_inited){
+		int i;
+		for(i=0; i<LOCK_FDS_N; i++){
+			pthread_mutex_init(&lock_fds[i], NULL);
+		}
+		lock_fds_inited = 1;
+	}
+
+	pthread_mutex_lock(&lock_fds[ fd % LOCK_FDS_N ]);
+}
+
+static void
+unlock_fd(int fd)
+{
+	pthread_mutex_unlock(&lock_fds[ fd % LOCK_FDS_N ]);
+}
+
 char *
 sock_cli_call(int fd, int cmd, int args_sz, char *args, int *rets_sz, char *rets)
 {
 	int sz;
 	char *buf;
 
+	lock_fd(fd);
+
 	write_n(fd, &cmd, sizeof(cmd));
 	write_n(fd, &args_sz, sizeof(args_sz));
 	if(args_sz > 0){
@@ -185,6 +211,9 @@
 	if(rets_sz){
 		*rets_sz = sz;
 	}
+
+	unlock_fd(fd);
+
 	return buf;
 	/*
 		need free_or_stk(buf, rets_sz)
diff -urN rt_v37/srvs.py rt_v38/srvs.py
--- rt_v37/srvs.py	2018-05-11 05:48:58.000000000 +0900
+++ rt_v38/srvs.py	2018-05-16 23:42:46.000000000 +0900
@@ -101,6 +101,13 @@
 	if name not in names:
 		print('srvs.kill ? ' + name)
 		return
+
+	s = 'lock_' + name
+	if name != 'srv.val':
+		boot_conn_val()
+		while not val.cli.s_try_lock(s):
+			ut.sleep(1)
+
 	if get_pid(name) < 0:
 		cmd = get_cmd(name)
 		print('boot ' + cmd)
@@ -109,6 +116,9 @@
 		pid = proc.pid
 		set_pid(name, pid)
 
+	if name != 'srv.val':
+		val.cli.s_unlock(s)
+
 def setup():
 	boot_conn_val()
 	for (name, inf) in infs[1:]:
diff -urN rt_v37/ut.py rt_v38/ut.py
--- rt_v37/ut.py	2018-05-12 12:03:56.000000000 +0900
+++ rt_v38/ut.py	2018-05-16 23:42:46.000000000 +0900
@@ -36,6 +36,7 @@
 	return v
 
 dic_cache = lambda d, k, f_v: d.get(k) if k in d else dic_set( d, k, f_v() )
+dic_cache_pop = lambda d, k, def_val=None: d.pop(k) if k in d else def_val
 
 if_not_set = lambda d, k, v: dic_cache(d, k, lambda : v)
 
diff -urN rt_v37/val.py rt_v38/val.py
--- rt_v37/val.py	2018-05-06 14:01:24.000000000 +0900
+++ rt_v38/val.py	2018-05-16 23:42:46.000000000 +0900
@@ -86,7 +86,7 @@
 	(sinf, v) = pks.ref(sinf, v, idxs)
 	return (sinf, v)
 
-def set_prop_bytes_idxs(s, idxs, pkd_byets):
+def set_prop_bytes_idxs(s, idxs, pkd_bytes):
 	org_str = get_prop_typ_str_idxs(s, idxs)
 
 	if not idxs:
@@ -121,6 +121,19 @@
 	v = get_prop_idxs_v(s, idxs)
 	return v_len(v)
 
+
+# prop lock
+
+def s_try_lock(s):
+	if has_prop(s):
+		return 0
+	typ_str = 'i4'
+	set_prop_bytes( s, typ_str, pks.pack_org_str(typ_str, 1) )
+	return 1
+
+def s_unlock(s):
+	del_prop(s)
+
 cmd_infs = [
 	{ 'cmd': 'geti', 'func': geti, 'args': '(str)', 'rets': 'i4' },
 	{ 'cmd': 'gets', 'func': gets, 'args': '(i4)', 'rets': 'str' },
@@ -143,6 +156,10 @@
 	{ 'cmd': 'get_prop_bytes_idxs', 'func': get_prop_bytes_idxs, 'args': '(str,[i4])', 'rets': '(str,bytes)' },
 	{ 'cmd': 'get_prop_typ_str_idxs', 'func': get_prop_typ_str_idxs, 'args': '(str,[i4])', 'rets': 'str' },
 	{ 'cmd': 'get_prop_n_idxs', 'func': get_prop_n_idxs, 'args': '(str,[i4])', 'rets': 'i4' },
+
+	# prop lock
+	{ 'cmd': 's_try_lock', 'func': s_try_lock, 'args': '(str)', 'rets': 'i4' },
+	{ 'cmd': 's_unlock', 'func': s_unlock, 'args': '(str)' },
 ]
 
 def new_client():