diff --git a/code/sys_nicmonitor/README b/code/sys_nicmonitor/README
index 5c04966..5f208ab 100644
--- a/code/sys_nicmonitor/README
+++ b/code/sys_nicmonitor/README
@@ -75,6 +75,12 @@ make runtest
 =======＝
 
 版本说明：
+--V1.21 --
+  2019-09-05
+  1）修复问题：monitor_interval参数溢出导致cpu 100%
+    问题描述：当monitor_interval参数配置为1000时，出现进程cpu占用100%的问题
+    解决办法：增加对monitor_interval配置的检测和限制
+
 --V1.9 --
   2013-08-12
   1）修复问题：占用内存快速累加，导致内存占用很大
diff --git a/code/sys_nicmonitor/mnic.c b/code/sys_nicmonitor/mnic.c
index c33c922..e6aec95 100644
--- a/code/sys_nicmonitor/mnic.c
+++ b/code/sys_nicmonitor/mnic.c
@@ -119,10 +119,10 @@ CONFIG_FILE_ST conf;
 
 char myconf[][64] = {
 	"domain",			// 0
-	"serv",				// 1 
+	"serv",				// 1
 	"event",			// 2
 	"udpport",			// 3
-	"sys_netcard_shm_path",		// 4 
+	"sys_netcard_shm_path",		// 4
 	"sys_netcard_sem_path",		// 5
 	"monitor_interval",		// 6
 	"write_interval",		// 7
@@ -151,7 +151,7 @@ static const configoption_t options[] = {
 	{myconf[9],  ARG_INT, cb_int, NULL, CTX_ALL},
 	{myconf[10], ARG_INT, cb_int, NULL, CTX_ALL},
 	{myconf[11], ARG_STR, cb_str, NULL, CTX_ALL},
-	{myconf[12], ARG_STR, cb_str, NULL, CTX_ALL},       
+	{myconf[12], ARG_STR, cb_str, NULL, CTX_ALL},
 	{myconf[13],  ARG_STR, cb_str, NULL, CTX_ALL},
 	{myconf[14],  ARG_INT, cb_int, NULL, CTX_ALL},
 	{myconf[15],  ARG_INT, cb_int, NULL, CTX_ALL},
@@ -191,7 +191,7 @@ static void *record_log_thread( void *arg )
 	log_thread_exit = 0;
 
 	log_fp = fopen(log_path, "a");
-	
+
 	while( !log_thread_exit ) {
 		if( !log_fp ) {
 			log_fp = fopen(log_path, "a");
@@ -233,7 +233,7 @@ static void *record_log_thread( void *arg )
 	log_prepare = NULL;
 	log_writing = NULL;
 
-	return NULL;	
+	return NULL;
 }
 
 /* write error in logfile */
@@ -266,7 +266,7 @@ void record_log(char *str)
 		if(fwrite(log_str, 1, strlen(log_str), log_fp) < 1){
 		}
 		fclose(log_fp);
-	}	
+	}
 #else
 	static int log_thread_started = 0;
 	time_t tamp;
@@ -305,9 +305,9 @@ void record_log(char *str)
 		log_prepare[log_idx] = keepstr;
 		log_idx++;
 	}
-	LOG_UNLOCK;	
+	LOG_UNLOCK;
 
-#endif	
+#endif
 }
 
 #else
@@ -385,14 +385,14 @@ static void init_shm(SHM **ptr, CONFIG_FILE_ST *p)
 	share_key = 0x1d5010;
 
 #if 0
-		snprintf( error_str, sizeof( error_str ), 
+		snprintf( error_str, sizeof( error_str ),
 				"MSG: sys_nic, shm, size:%d, key:0x%x(%d)\n", size, share_key, share_key);
 		record_log(error_str);
 #endif
 
 	global_share_id = shmget( share_key, size, IPC_CREAT|0666 );
 	if( global_share_id == -1 ) {
-		snprintf( error_str, sizeof( error_str ), 
+		snprintf( error_str, sizeof( error_str ),
 				"EMERG: fail shmget, %s, 0x%x\n", strerror(errno), share_key);
 		record_log(error_str);
         	return;
@@ -400,7 +400,7 @@ static void init_shm(SHM **ptr, CONFIG_FILE_ST *p)
 
 	shmptr = shmat( global_share_id, NULL, 0 );
 	if( shmptr == (void *)-1 ) {
-		snprintf( error_str, sizeof( error_str ), 
+		snprintf( error_str, sizeof( error_str ),
 				"EMERG: fail shmat, %s, %s\n", strerror(errno), path);
 		record_log(error_str);
         	return;
@@ -450,7 +450,7 @@ static void release_sem(int semid)
 	char error_str[200];
 	struct sembuf unlock;
 
-	unlock.sem_num = 0; 
+	unlock.sem_num = 0;
 	unlock.sem_op = 1;
 	unlock.sem_flg = SEM_UNDO;
 
@@ -616,7 +616,7 @@ static void send_inc_info_one(NETCARD_INFO *net, int semid, SHM *ptr)
 		if(!strncmp(ptr->info[i].charname, net->charname, NIC_NAME_LEN)){
 			get_sem(semid);
 			memcpy(&ptr->info[i], net, sizeof(NETCARD_INFO));
-			release_sem(semid);	
+			release_sem(semid);
 		}
 	}
 }
@@ -639,7 +639,7 @@ static void *send_inc_info(void *p)
 		return NULL;
 	}
 	s_time.tv_sec = ptr->conf->write_interval;
-	s_time.tv_nsec = 0;	
+	s_time.tv_nsec = 0;
 
 	/* copy all net_info*/
 	while(1){
@@ -738,7 +738,7 @@ static void *cacu_flow(void *p)
 			//tx_flow,rx_flow,
 			 rx_flow=(curr->info.rx_bytes -rx_bytes[i])/ptr->mem.conf->flow_interval;
 			 tx_flow=(curr->info.tx_bytes -tx_bytes[i])/ptr->mem.conf->flow_interval;
-			
+
 			if(!strncmp(curr->info.charname, "bond", 4)){
 				count_t = get_netcard_count(curr->info.charname);
 			}else {
@@ -772,8 +772,8 @@ static void *cacu_flow(void *p)
 					if(count_no[i] == 0){
 						send_inc_info_one(&curr->info, ptr->mem.semid, ptr->mem.shm_ptr);
 						if( sys_nic_debug ) {
-							snprintf(error_str, sizeof(error_str), 
-									"NOTICE: %s flow is abnormal, summit is %d, average flow is %lld , rx_flow is %lld , tx_flow is %lld !\n", 
+							snprintf(error_str, sizeof(error_str),
+									"NOTICE: %s flow is abnormal, summit is %d, average flow is %lld , rx_flow is %lld , tx_flow is %lld !\n",
 									curr->info.charname, summit, curr->info.average_flow,rx_flow,tx_flow);
 						} else {
 							snprintf(error_str, sizeof(error_str), "NOTICE: %s flow is abnormal !\n", curr->info.charname);
@@ -1082,7 +1082,7 @@ void sig_handler(int sig)
 		record_log(err_str);
 	}
 #endif
-	//	semctl(sem_id, 0, IPC_RMID);	
+	//	semctl(sem_id, 0, IPC_RMID);
 
 	//	snprintf(err_str, sizeof(err_str), "NOTICE: process exit by signal %d\n", sig);
 	//	record_log(err_str);
@@ -1255,6 +1255,11 @@ int get_conf()
 		conf.udpport = 15000;
 	if(conf.monitor_interval == 0)
 		conf.monitor_interval = 100;
+	if(conf.monitor_interval >= 1000){
+        sprintf(tmp_str,"%s","Error monitor_interval must less than 1000\n");
+		record_log(tmp_str);
+		return -2;
+	}
 	if(conf.write_interval == 0)
 		conf.write_interval = 300;
 	if(conf.flow_interval == 0)
@@ -1436,7 +1441,7 @@ int get_netcard_status(NETCARD_INFO_ST *listp)
 			return NIC_UNLINKABLE;
 	}
 	else{
-		if(listp->status ==  NIC_UNLINKABLE) 
+		if(listp->status ==  NIC_UNLINKABLE)
 			return NIC_UNLINKABLE;
 	}
 
@@ -1505,7 +1510,7 @@ int main(int argc, char ** argv)
 	int  ret = 0, proc_stat = 0;
 	unsigned int i = 0;
 	int nic_status;
-	int sys_time_stamp = 0; 
+	int sys_time_stamp = 0;
 	char *retp = NULL;
 	char *str = NULL;
 	char bond[128];
@@ -1534,10 +1539,10 @@ int main(int argc, char ** argv)
 	char log_record[125]={0};
 	char *dir_memory;
 	int shm_key =0x1d6010;
-	
+
 	if( getenv("SYS_NIC_DEBUG") ) {
 		sys_nic_debug = 1;
-	} 
+	}
 
 	memset(&conf, 0, sizeof(CONFIG_FILE_ST));
 	if(isrun(argv[0]) == 1){
@@ -1557,9 +1562,9 @@ int main(int argc, char ** argv)
 	sigaddset(&sig.sa_mask, SIGINT);
 	sigaddset(&sig.sa_mask, SIGTERM);
 	sig.sa_flags = 0;
-	sigaction(SIGTERM, &sig, NULL); 
-	sigaction(SIGINT, &sig, NULL); 
-	sigaction(SIGSEGV, &sig, NULL); 
+	sigaction(SIGTERM, &sig, NULL);
+	sigaction(SIGINT, &sig, NULL);
+	sigaction(SIGSEGV, &sig, NULL);
 
 	/* create dir  file path */
 	if((user = getpwnam("d5000")) != NULL){
@@ -1615,11 +1620,16 @@ int main(int argc, char ** argv)
 	log_time.tv_nsec = 1000000;
 	while(log_flag)nanosleep(&log_time, NULL);
 
-	/* sure the process is started */
-	snprintf(error_str, sizeof(error_str), "NOTICE: %s V%s is started !\n", process_name, MNIC_VERSION);
-	record_log(error_str);
+	if(get_conf()==-2){
+        	printf("Error monitor_interval must less than 1000\n");
+		return -1;
+	} else{
+		snprintf(error_str, sizeof(error_str), "NOTICE: %s V%s is started !\n", process_name, MNIC_VERSION);
+		record_log(error_str);
+	}
+
+	/* sure the process is started */
 
-	get_conf();
 
 	if(shm_path){
 		printf("shm_path:%s\n",shm_path);
@@ -1648,7 +1658,7 @@ int main(int argc, char ** argv)
 
 	/* get broadcast address*/
 	if((ret = get_broad_ip()) != 0)
-		return -1;	
+		return -1;
 	if((ret = create_name_list(&all_name_list, &opt_name_list)) != 0)
 		return -1;
 	/* get hostname */
@@ -1787,7 +1797,7 @@ int main(int argc, char ** argv)
 	munmap(shm_ptr, sizeof(SHM));
 #else
 	{
-	
+
 	void *shmptr = shm_ptr;
 #if 0
 	snprintf(error_str, sizeof(error_str), "NOTICE: free shm %p, glo:%p\n", shmptr, global_shmptr);
@@ -1803,7 +1813,7 @@ int main(int argc, char ** argv)
 
 		is_last = *ref_count == 1?1:0;
 #if 0
-	snprintf(error_str, sizeof(error_str), "NOTICE: sys_nic, size:%d, ref_count: %d, last:%d\n", 
+	snprintf(error_str, sizeof(error_str), "NOTICE: sys_nic, size:%d, ref_count: %d, last:%d\n",
 					size, *ref_count, is_last);
 	record_log(error_str);
 #endif
@@ -1819,7 +1829,7 @@ int main(int argc, char ** argv)
 //			global_share_id = -1;
 //		}
 	}
-	}	
+	}
 #endif
 	return 0;
 }
diff --git a/code/sys_nicmonitor/version.h b/code/sys_nicmonitor/version.h
index 26791ed..256feb1 100644
--- a/code/sys_nicmonitor/version.h
+++ b/code/sys_nicmonitor/version.h
@@ -1,5 +1,5 @@
 // version=1.20
 #ifndef MNIC_VERSION
-	#define MNIC_VERSION "1.20"
+	#define MNIC_VERSION "1.21"
 #endif