Add lru evict count for the idle loop (innobase)

port of work by dveeden:
https://github.com/dveeden/mysql-server/commit/555ca34958a8ed191f34eeb2333e0d7c30e12fce

storage/innobase/include/srv0mon.h

@@ -378,7 +378,8 @@ enum monitor_id_t {
 	MONITOR_SRV_MEM_VALIDATE_MICROSECOND,
 	MONITOR_SRV_PURGE_MICROSECOND,
 	MONITOR_SRV_DICT_LRU_MICROSECOND,
-	MONITOR_SRV_DICT_LRU_EVICT_COUNT,
+	MONITOR_SRV_DICT_LRU_EVICT_COUNT_ACTIVE,
+	MONITOR_SRV_DICT_LRU_EVICT_COUNT_IDLE,
 	MONITOR_SRV_CHECKPOINT_MICROSECOND,
 	MONITOR_OVLD_SRV_DBLWR_WRITES,
 	MONITOR_OVLD_SRV_DBLWR_PAGES_WRITTEN,

storage/innobase/srv/srv0mon.cc

@@ -1196,10 +1196,15 @@ static monitor_info_t	innodb_counter_info[] =
 	 MONITOR_NONE,
 	 MONITOR_DEFAULT_START, MONITOR_SRV_DICT_LRU_MICROSECOND},
 
-	{"innodb_dict_lru_count", "server",
-	 "Number of tables evicted from DICT LRU list",
+	{"innodb_dict_lru_count_active", "server",
+	 "Number of tables evicted from DICT LRU list in the active loop",
 	 MONITOR_NONE,
-	 MONITOR_DEFAULT_START, MONITOR_SRV_DICT_LRU_EVICT_COUNT},
+	 MONITOR_DEFAULT_START, MONITOR_SRV_DICT_LRU_EVICT_COUNT_ACTIVE},
+
+	{"innodb_dict_lru_count_idle", "server",
+	 "Number of tables evicted from DICT LRU list in the idle loop",
+	 MONITOR_NONE,
+	 MONITOR_DEFAULT_START, MONITOR_SRV_DICT_LRU_EVICT_COUNT_IDLE},
 
 	{"innodb_checkpoint_usec", "server",
 	 "Time (in microseconds) spent by master thread to do checkpoint",

storage/innobase/srv/srv0srv.cc

@@ -2337,7 +2337,7 @@ srv_master_do_active_tasks(void)
 		srv_main_thread_op_info = "enforcing dict cache limit";
 		n_evicted = srv_master_evict_from_table_cache(50);
 		MONITOR_INC_VALUE(
-			MONITOR_SRV_DICT_LRU_EVICT_COUNT, n_evicted);
+			MONITOR_SRV_DICT_LRU_EVICT_COUNT_ACTIVE, n_evicted);
 		MONITOR_INC_TIME_IN_MICRO_SECS(
 			MONITOR_SRV_DICT_LRU_MICROSECOND, counter_time);
 	}
@@ -2369,6 +2369,7 @@ srv_master_do_idle_tasks(void)
 /*==========================*/
 {
 	ullint	counter_time;
+	ulint	n_evicted = 0;
 
 	++srv_main_idle_loops;
 
@@ -2406,7 +2407,9 @@ srv_master_do_idle_tasks(void)
 	}
 
 	srv_main_thread_op_info = "enforcing dict cache limit";
-	srv_master_evict_from_table_cache(100);
+	n_evicted = srv_master_evict_from_table_cache(100);
+        MONITOR_INC_VALUE(
+                MONITOR_SRV_DICT_LRU_EVICT_COUNT_IDLE, n_evicted);
 	MONITOR_INC_TIME_IN_MICRO_SECS(
 		MONITOR_SRV_DICT_LRU_MICROSECOND, counter_time);