diff --git a/guc.c b/guc.c
index 88105fa..53f3906 100644
--- a/guc.c
+++ b/guc.c
@@ -38,12 +38,12 @@ init_guc(void)
 		.guc_restart = true
 	};
 	conf[i++] = (GucVariable) { 
-		.guc_name = "pg_stat_monitor.pgsm_track",
-		.guc_desc = "Selects which statements are tracked by pg_stat_monitor.",
-		.guc_default = 0,
+		.guc_name = "pg_stat_monitor.pgsm_enable",
+		.guc_desc = "Enable/Disable stistics collector.",
+		.guc_default = 1,
 		.guc_min = 0,
 		.guc_max = 0,
-		.guc_restart = false
+		.guc_restart = true
 	};
 	conf[i++] = (GucVariable) { 
 		.guc_name = "pg_stat_monitor.pgsm_track_utility",
@@ -138,7 +138,7 @@ init_guc(void)
 							NULL);
 
 	DefineCustomIntVariable("pg_stat_monitor.pgsm_query_max_len",
-							"Sets the maximum length of query",
+							"Sets the maximum length of query.",
 							NULL,
 							&PGSM_QUERY_MAX_LEN,
 							1024,
@@ -150,12 +150,11 @@ init_guc(void)
 							NULL,
 							NULL);
 
-	DefineCustomEnumVariable("pg_stat_monitor.pgsm_track",
-							 "Selects which statements are tracked by pg_stat_monitor.",
+	DefineCustomBoolVariable("pg_stat_monitor.pgsm_enable",
+							 "Enable/Disable the statis collector.",
 							 NULL,
-							 &PGSM_TRACK,
-							 PGSM_TRACK_TOP,
-							 track_options,
+							 (bool*)&PGSM_ENABLED,
+							 true,
 							 PGC_SUSET,
 							 0,
 							 NULL,
@@ -167,7 +166,7 @@ init_guc(void)
 							 NULL,
 							 (bool*)&PGSM_TRACK_UTILITY,
 							 true,
-							 PGC_SUSET,
+							 PGC_USERSET,
 							 0,
 							 NULL,
 							 NULL,
@@ -178,7 +177,7 @@ init_guc(void)
 							 NULL,
 							 (bool*)&PGSM_NORMALIZED_QUERY,
 							 true,
-							 PGC_SUSET,
+							 PGC_USERSET,
 							 0,
 							 NULL,
 							 NULL,
diff --git a/pg_stat_monitor.c b/pg_stat_monitor.c
index a9cf05b..9033095 100644
--- a/pg_stat_monitor.c
+++ b/pg_stat_monitor.c
@@ -481,7 +481,7 @@ pgss_ExecutorStart(QueryDesc *queryDesc, int eflags)
 	 * counting of optimizable statements that are directly contained in
 	 * utility statements.
 	 */
-	if (PGSS_ENABLED() && queryDesc->plannedstmt->queryId != UINT64CONST(0))
+	if (PGSM_ENABLED && queryDesc->plannedstmt->queryId != UINT64CONST(0))
 	{
 		/*
 		 * Set up to track total elapsed time in ExecutorRun.  Make sure the
@@ -556,7 +556,7 @@ pgss_ExecutorEnd(QueryDesc *queryDesc)
 	float   stime;
 	uint64	queryId = queryDesc->plannedstmt->queryId;
 
-	if (queryId != UINT64CONST(0) && queryDesc->totaltime && PGSS_ENABLED())
+	if (queryId != UINT64CONST(0) && queryDesc->totaltime && PGSM_ENABLED)
 	{
 		/*
 		 * Make sure stats accumulation is done.  (Note: it's okay if several
diff --git a/pg_stat_monitor.h b/pg_stat_monitor.h
index 85f1fd7..a0e33ba 100644
--- a/pg_stat_monitor.h
+++ b/pg_stat_monitor.h
@@ -325,32 +325,13 @@ typedef struct pgssJumbleState
 	int			highest_extern_param_id;
 } pgssJumbleState;
 
-typedef enum
-{
-	PGSM_TRACK_NONE,			/* track no statements */
-	PGSM_TRACK_TOP,				/* only top level statements */
-	PGSM_TRACK_ALL				/* all statements, including nested ones */
-} PGSSTRACKlEVEL;
-
-static const struct config_enum_entry track_options[] =
-{
-	{"none", PGSM_TRACK_NONE, false},
-	{"top", PGSM_TRACK_TOP, false},
-	{"all", PGSM_TRACK_ALL, false},
-	{NULL, 0, false}
-};
-
-#define PGSS_ENABLED() \
-	(PGSM_TRACK == PGSM_TRACK_ALL || \
-	(PGSM_TRACK == PGSM_TRACK_TOP && nested_level == 0))
-
 /* guc.c */
 void init_guc(void);
 
 /*---- GUC variables ----*/
 #define PGSM_MAX conf[0].guc_variable
 #define PGSM_QUERY_MAX_LEN conf[1].guc_variable
-#define PGSM_TRACK conf[2].guc_variable
+#define PGSM_ENABLED conf[2].guc_variable
 #define PGSM_TRACK_UTILITY conf[3].guc_variable
 #define PGSM_NORMALIZED_QUERY conf[4].guc_variable
 #define PGSM_MAX_BUCKETS conf[5].guc_variable