From 4ec357b419efe15d371d22fd9127bc2677519e7d Mon Sep 17 00:00:00 2001
From: Alexander Zalyalov <zalyalov@ydb.tech>
Date: Tue, 16 Jan 2024 17:47:46 +0000
Subject: [PATCH] add sensor for metadata cache

---
 .../run/kikimr_services_initializers.cpp         |  2 +-
 ydb/core/grpc_services/db_metadata_cache.h       | 16 ++++++++++++----
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/ydb/core/driver_lib/run/kikimr_services_initializers.cpp b/ydb/core/driver_lib/run/kikimr_services_initializers.cpp
index 0e2c31332004..f327d04ad7c5 100644
--- a/ydb/core/driver_lib/run/kikimr_services_initializers.cpp
+++ b/ydb/core/driver_lib/run/kikimr_services_initializers.cpp
@@ -2677,7 +2677,7 @@ TDatabaseMetadataCacheInitializer::TDatabaseMetadataCacheInitializer(const TKiki
 void TDatabaseMetadataCacheInitializer::InitializeServices(NActors::TActorSystemSetup* setup, const NKikimr::TAppData* appData) {
     setup->LocalServices.emplace_back(
         MakeDatabaseMetadataCacheId(NodeId),
-        TActorSetupCmd(CreateDatabaseMetadataCache(appData->TenantName), TMailboxType::HTSwap, appData->UserPoolId));
+        TActorSetupCmd(CreateDatabaseMetadataCache(appData->TenantName, appData->Counters), TMailboxType::HTSwap, appData->UserPoolId));
 }
 
 TGraphServiceInitializer::TGraphServiceInitializer(const TKikimrRunConfig& runConfig)
diff --git a/ydb/core/grpc_services/db_metadata_cache.h b/ydb/core/grpc_services/db_metadata_cache.h
index fad53bf04b5b..f28f3bfe6546 100644
--- a/ydb/core/grpc_services/db_metadata_cache.h
+++ b/ydb/core/grpc_services/db_metadata_cache.h
@@ -4,6 +4,7 @@
 #include <ydb/library/actors/core/actor_bootstrapped.h>
 #include <ydb/library/actors/core/hfunc.h>
 #include <ydb/core/base/appdata.h>
+#include <ydb/core/base/counters.h>
 #include <ydb/core/base/feature_flags.h>
 #include <ydb/core/base/domain.h>
 #include <ydb/core/base/statestorage.h>
@@ -44,6 +45,9 @@ class TDatabaseMetadataCache : public TActorBootstrapped<TDatabaseMetadataCache>
     TActorId PublishActor;
     TActorId SubscribeActor;
     bool RequestInProgress = false;
+    ::NMonitoring::TDynamicCounterPtr Counters;
+    static const inline TString HEALTHCHECK_REQUESTS_MADE_COUNTER = "DbMetadataCache/HealthCheckRequestsMade";
+    static const inline TString HEALTHCHECK_REQUESTS_ANSWERED_COUNTER = "DbMetadataCache/HealthCheckRequestsAnswered";
 
     void SendRequest() {
         if (RequestInProgress) {
@@ -54,12 +58,14 @@ class TDatabaseMetadataCache : public TActorBootstrapped<TDatabaseMetadataCache>
         request->Database = Path;
         request->Request.set_return_verbose_status(true);
         Send(NHealthCheck::MakeHealthCheckID(), request.release());
+        Counters->GetCounter(HEALTHCHECK_REQUESTS_MADE_COUNTER, true)->Inc();
     }
 
     void Reply(TActorId client) {
         auto response = std::make_unique<NHealthCheck::TEvSelfCheckResultProto>();
         response->Record = *Result;
         Send(client, response.release());
+        Counters->GetCounter(HEALTHCHECK_REQUESTS_ANSWERED_COUNTER, true)->Inc();
     }
 
     void RefreshCache() {
@@ -136,9 +142,11 @@ class TDatabaseMetadataCache : public TActorBootstrapped<TDatabaseMetadataCache>
     }
 
 public:
-    TDatabaseMetadataCache(const TString& path) : Path(path)
-                                                , BoardPath(MakeDatabaseMetadataCacheBoardPath(Path))
+    TDatabaseMetadataCache(const TString& path,
+                           const ::NMonitoring::TDynamicCounterPtr& counters) : Path(path)
+                                                                              , BoardPath(MakeDatabaseMetadataCacheBoardPath(Path))
     {
+        Counters = GetServiceCounters(counters, "utils")->GetSubgroup("database", path);
     }
 
     static ui32 PickActiveNode(const TBoardInfoEntries& infoEntries) {
@@ -223,8 +231,8 @@ inline TActorId MakeDatabaseMetadataCacheId(ui32 nodeId) {
     return TActorId(nodeId, "METACACHE");
 }
 
-inline std::unique_ptr<IActor> CreateDatabaseMetadataCache(const TString& path) {
-    return std::unique_ptr<IActor>(new TDatabaseMetadataCache(path));
+inline std::unique_ptr<IActor> CreateDatabaseMetadataCache(const TString& path, const ::NMonitoring::TDynamicCounterPtr& counters) {
+    return std::unique_ptr<IActor>(new TDatabaseMetadataCache(path, counters));
 }
 
 inline std::optional<TActorId> ResolveActiveDatabaseMetadataCache(const TMap<TActorId, TEvStateStorage::TBoardInfoEntry>& infoEntries) {