split metric

dbms/src/Common/CurrentMetrics.cpp

@@ -12,7 +12,8 @@
     M(BackgroundPoolTask, "Number of active tasks in BackgroundProcessingPool (merges, mutations, fetches, or replication queue bookkeeping)") \
     M(BackgroundMovePoolTask, "Number of active tasks in BackgroundProcessingPool for moves") \
     M(BackgroundSchedulePoolTask, "Number of active tasks in BackgroundSchedulePool. This pool is used for periodic ReplicatedMergeTree tasks, like cleaning old data parts, altering data parts, replica re-initialization, etc.") \
-    M(CacheDictionaryUpdateQueueSize, "Number of 'units' (a set of keys) in update queue in CacheDictionaries.") \
+    M(CacheDictionaryUpdateQueueBatches, "Number of 'batches' (a set of keys) in update queue in CacheDictionaries.") \
+    M(CacheDictionaryUpdateQueueKeys, "Exact number of keys in update queue in CacheDictionaries.") \
     M(DiskSpaceReservedForMerge, "Disk space reserved for currently running background merges. It is slightly more than the total size of currently merging parts.") \
     M(DistributedSend, "Number of connections to remote servers sending data that was INSERTed into Distributed tables. Both synchronous and asynchronous mode.") \
     M(QueryPreempted, "Number of queries that are stopped and waiting due to 'priority' setting.") \

dbms/src/Dictionaries/CacheDictionary.h

@@ -24,7 +24,8 @@
 
 namespace CurrentMetrics
 {
-    extern const Metric CacheDictionaryUpdateQueueSize;
+    extern const Metric CacheDictionaryUpdateQueueBatches;
+    extern const Metric CacheDictionaryUpdateQueueKeys;
 }
 
 
@@ -356,12 +357,14 @@ private:
                 AbsentIdHandler absent_id_handler_) :
                 requested_ids(std::move(requested_ids_)),
                 present_id_handler(present_id_handler_),
-                absent_id_handler(absent_id_handler_) {}
+                absent_id_handler(absent_id_handler_),
+                alive_keys(CurrentMetrics::CacheDictionaryUpdateQueueKeys, requested_ids.size()){}
 
         explicit UpdateUnit(std::vector<Key> requested_ids_) :
                 requested_ids(std::move(requested_ids_)),
                 present_id_handler([](Key, size_t){}),
-                absent_id_handler([](Key, size_t){}) {}
+                absent_id_handler([](Key, size_t){}),
+                alive_keys(CurrentMetrics::CacheDictionaryUpdateQueueKeys, requested_ids.size()){}
 
         std::vector<Key> requested_ids;
         PresentIdHandler present_id_handler;
@@ -371,7 +374,8 @@ private:
         std::exception_ptr current_exception{nullptr};
 
         /// While UpdateUnit is alive, it is accounted in update_queue size.
-        CurrentMetrics::Increment alive_update_unit{CurrentMetrics::CacheDictionaryUpdateQueueSize};
+        CurrentMetrics::Increment alive_batch{CurrentMetrics::CacheDictionaryUpdateQueueBatches};
+        CurrentMetrics::Increment alive_keys;
     };
 
     using UpdateUnitPtr = std::shared_ptr<UpdateUnit>;