diff --git a/inc/Maat_rule.h b/inc/Maat_rule.h
index d22aabd..1bfb93d 100644
--- a/inc/Maat_rule.h
+++ b/inc/Maat_rule.h
@@ -158,7 +158,8 @@ enum MAAT_INIT_OPT
 									//This option also disables background update.
 	MAAT_OPT_ENABLE_UPDATE,			//VALUE is interger, SIZE=sizeof(int). 1: Enabled, 0:Disabled.  DEFAULT: Backgroud update is enabled. Runtime setting is allowed.
 	MAAT_OPT_ACCEPT_TAGS,			//VALUE is a const char*, MUST end with '\0', SIZE= strlen(string+'\0')+1. Format is a JSON, e.g.{"tags":[{"tag":"location","value":"Beijing/ChaoYang/Huayan/22A"},{"tag":"isp","value":"telecom"}]}
-	MAAT_OPT_FOREIGN_CONT_DIR		//VALUE is a const char*, MUST end with '\0', SIZE= strlen(string+'\0')+1. Specifies a local diretory to store foreign content. Default: []table_info_path]_files
+	MAAT_OPT_FOREIGN_CONT_DIR,		//VALUE is a const char*, MUST end with '\0', SIZE= strlen(string+'\0')+1. Specifies a local diretory to store foreign content. Default: []table_info_path]_files
+	MAAT_OPT_GARBAGE_COLLECTION_TIMEOUT_MS //VALUE is interger, SIZE=sizeof(int). DEFAULT:10,000 milliseconds.
 };
 //return -1 if failed, return 0 on success;
 int Maat_set_feather_opt(Maat_feather_t feather,enum MAAT_INIT_OPT  type,const void* value,int size);
diff --git a/src/entry/Maat_api.cpp b/src/entry/Maat_api.cpp
index 8756fd2..60095de 100644
--- a/src/entry/Maat_api.cpp
+++ b/src/entry/Maat_api.cpp
@@ -547,8 +547,9 @@ Maat_feather_t Maat_feather(int max_thread_num,const char* table_info_path,void*
 	feather->logger=logger;
 	feather->scan_thread_num=max_thread_num;
 	
-	feather->effect_interval_ms=60*1000;
-	feather->scan_interval_ms=1*1000;
+	feather->rule_effect_interval_ms=60*1000;
+	feather->rule_update_checking_interval_ms=1*1000;
+	feather->garbage_collection_timeout_ms=10*1000;
 	feather->rule_scan_type=0;
 	feather->thread_call_cnt=alignment_int64_array_alloc(max_thread_num);
 	feather->outer_mid_cnt=alignment_int64_array_alloc(max_thread_num);
@@ -621,7 +622,7 @@ int Maat_set_feather_opt(Maat_feather_t feather,enum MAAT_INIT_OPT type,const vo
 			{
 				return -1;
 			}
-			_feather->effect_interval_ms=intval;
+			_feather->rule_effect_interval_ms=intval;
 			break;
 		case MAAT_OPT_SCANDIR_INTERVAL_MS:
 			intval=*(const int*)value;
@@ -629,8 +630,17 @@ int Maat_set_feather_opt(Maat_feather_t feather,enum MAAT_INIT_OPT type,const vo
 			{
 				return -1;
 			}
-			_feather->scan_interval_ms=intval;
+			_feather->rule_update_checking_interval_ms=intval;
 			break;
+		case MAAT_OPT_GARBAGE_COLLECTION_TIMEOUT_MS:
+			intval=*(const int*)value;
+			if(size!=sizeof(int)||intval<0)
+			{
+				return -1;
+			}
+			_feather->garbage_collection_timeout_ms=intval;
+			break;
+
 		case MAAT_OPT_FULL_CFG_DIR:			
 			assert(_feather->input_mode==SOURCE_NONE);
 			if(size>(int)sizeof(_feather->iris_ctx.full_dir))
@@ -846,8 +856,9 @@ void maat_read_full_config(_Maat_feather_t* _feather)
 int Maat_initiate_feather(Maat_feather_t feather)
 {
 	_Maat_feather_t* _feather=(_Maat_feather_t*)feather;
-	_feather->garbage_bin=Maat_garbage_bin_new(_feather->effect_interval_ms/1000+10);
-	system_cmd_mkdir(_feather->foreign_cont_dir);
+	system_cmd_mkdir(_feather->foreign_cont_dir);	
+	_feather->garbage_bin=Maat_garbage_bin_new(_feather->rule_effect_interval_ms/1000+_feather->garbage_collection_timeout_ms/1000);
+	
 	if(_feather->DEFERRED_LOAD_ON==0)
 	{
 		maat_read_full_config(_feather);
diff --git a/src/entry/Maat_rule.cpp b/src/entry/Maat_rule.cpp
index d7f54cc..e93d9ca 100644
--- a/src/entry/Maat_rule.cpp
+++ b/src/entry/Maat_rule.cpp
@@ -2477,7 +2477,7 @@ void maat_finish_cb(void* u_para)
 		feather->scanner->version=feather->maat_version;
 		expr_wait_q_cnt=MESA_lqueue_get_count(feather->scanner->region_update_q);
 		feather->postpone_q_size=expr_wait_q_cnt+feather->scanner->gie_update_q_size+feather->scanner->xx_plugin_update_q_size;
-		if(time(NULL)-feather->scanner->last_update_time>=feather->effect_interval_ms/1000)
+		if(time(NULL)-feather->scanner->last_update_time>=feather->rule_effect_interval_ms/1000)
 		{
 			do_scanner_update(feather->scanner,
 							feather->scan_thread_num,
@@ -2603,7 +2603,7 @@ void *thread_rule_monitor(void *arg)
 	pthread_mutex_unlock(&(feather->background_update_mutex));
 	while(feather->still_working)
 	{
-		usleep(feather->scan_interval_ms*1000);
+		usleep(feather->rule_update_checking_interval_ms*1000);
 		scan_dir_cnt++;
 		if(0==pthread_mutex_trylock(&(feather->background_update_mutex)))
 		{
@@ -2704,7 +2704,7 @@ void *thread_rule_monitor(void *arg)
 				expr_wait_q_cnt=MESA_lqueue_get_count(feather->scanner->region_update_q);
 				feather->postpone_q_size=expr_wait_q_cnt+feather->scanner->gie_update_q_size;
 				total_wait_rule_cnt=feather->postpone_q_size+feather->scanner->to_update_compile_cnt+feather->scanner->to_update_group_cnt;
-				if(total_wait_rule_cnt>0&&time(NULL)-feather->scanner->last_update_time>=feather->effect_interval_ms/1000)
+				if(total_wait_rule_cnt>0&&time(NULL)-feather->scanner->last_update_time>=feather->rule_effect_interval_ms/1000)
 				{
 					do_scanner_update(feather->scanner,
 									feather->scan_thread_num,
diff --git a/src/inc_internal/Maat_rule_internal.h b/src/inc_internal/Maat_rule_internal.h
index c92b944..0573579 100644
--- a/src/inc_internal/Maat_rule_internal.h
+++ b/src/inc_internal/Maat_rule_internal.h
@@ -290,8 +290,9 @@ struct _Maat_feather_t
 		struct source_redis_ctx mr_ctx;
 	};
 	int still_working;
-	int scan_interval_ms;
-	int effect_interval_ms;
+	int rule_update_checking_interval_ms;
+	int rule_effect_interval_ms;
+	int garbage_collection_timeout_ms;
 	int cumulative_update_off;
 	int stat_on;
 	int perf_on;