issue-3362 [Filestore] add a sensor for direct handles (#4150)

#3362

Author: neihar

cloud/filestore/libs/storage/tablet/tablet_actor.h

@@ -90,6 +90,7 @@ class TIndexTabletActor final
 
         std::atomic<i64> UsedSessionsCount{0};
         std::atomic<i64> UsedHandlesCount{0};
+        std::atomic<i64> UsedDirectHandlesCount{0};
         std::atomic<i64> UsedLocksCount{0};
 
         // Session stats
@@ -364,7 +365,8 @@ class TIndexTabletActor final
             const TBlobMetaMapStats& blobMetaMapStats,
             const TIndexTabletState::TBackpressureThresholds&
                 backpressureThresholds,
-            const TIndexTabletState::TBackpressureValues& backpressureValues);
+            const TIndexTabletState::TBackpressureValues& backpressureValues,
+            const THandlesStats& handlesStats);
         void UpdatePerformanceMetrics(
             TInstant now,
             const TDiagnosticsConfig& diagConfig,

cloud/filestore/libs/storage/tablet/tablet_actor_counters.cpp

@@ -345,6 +345,7 @@ void TIndexTabletActor::TMetrics::Register(
 
     REGISTER_AGGREGATABLE_SUM(UsedSessionsCount, EMetricType::MT_ABSOLUTE);
     REGISTER_AGGREGATABLE_SUM(UsedHandlesCount, EMetricType::MT_ABSOLUTE);
+    REGISTER_AGGREGATABLE_SUM(UsedDirectHandlesCount, EMetricType::MT_ABSOLUTE);
     REGISTER_AGGREGATABLE_SUM(UsedLocksCount, EMetricType::MT_ABSOLUTE);
     REGISTER_AGGREGATABLE_SUM(StatefulSessionsCount, EMetricType::MT_ABSOLUTE);
     REGISTER_AGGREGATABLE_SUM(StatelessSessionsCount, EMetricType::MT_ABSOLUTE);
@@ -568,7 +569,8 @@ void TIndexTabletActor::TMetrics::Update(
     const TInMemoryIndexStateStats& inMemoryIndexStateStats,
     const TBlobMetaMapStats& blobMetaMapStats,
     const TIndexTabletState::TBackpressureThresholds& backpressureThresholds,
-    const TIndexTabletState::TBackpressureValues& backpressureValues)
+    const TIndexTabletState::TBackpressureValues& backpressureValues,
+    const THandlesStats& handlesStats)
 {
     const ui32 blockSize = fileSystem.GetBlockSize();
 
@@ -580,6 +582,7 @@ void TIndexTabletActor::TMetrics::Update(
 
     Store(UsedSessionsCount, stats.GetUsedSessionsCount());
     Store(UsedHandlesCount, stats.GetUsedHandlesCount());
+    Store(UsedDirectHandlesCount, handlesStats.UsedDirectHandlesCount);
     Store(UsedLocksCount, stats.GetUsedLocksCount());
 
     Store(FreshBytesCount, stats.GetFreshBytesCount());
@@ -816,7 +819,8 @@ void TIndexTabletActor::RegisterStatCounters(TInstant now)
         GetInMemoryIndexStateStats(),
         GetBlobMetaMapStats(),
         BuildBackpressureThresholds(),
-        GetBackpressureValues());
+        GetBackpressureValues(),
+        GetHandlesStats());
 
     // TabletStartTimestamp is intialised once per tablet lifetime and thus it is
     // acceptable to set it in RegisterStatCounters if it is not set yet.
@@ -876,7 +880,8 @@ void TIndexTabletActor::HandleUpdateCounters(
         GetInMemoryIndexStateStats(),
         GetBlobMetaMapStats(),
         BuildBackpressureThresholds(),
-        GetBackpressureValues());
+        GetBackpressureValues(),
+        GetHandlesStats());
     SendMetricsToExecutor(ctx);
 
     UpdateCountersScheduled = false;

cloud/filestore/libs/storage/tablet/tablet_state.cpp

@@ -234,6 +234,13 @@ TMiscNodeStats TIndexTabletState::GetMiscNodeStats() const
     };
 }
 
+THandlesStats TIndexTabletState::GetHandlesStats() const
+{
+    return {
+        .UsedDirectHandlesCount = Impl->UsedDirectHandlesCount,
+    };
+}
+
 ui64 TIndexTabletState::CalculateExpectedShardCount() const
 {
     if (FileSystem.GetShardNo()) {

cloud/filestore/libs/storage/tablet/tablet_state.h

@@ -148,6 +148,11 @@ struct TMiscNodeStats
     i64 OrphanNodesCount{0};
 };
 
+struct THandlesStats
+{
+    i64 UsedDirectHandlesCount{0};
+};
+
 struct TWriteMixedBlocksResult
 {
     ui32 GarbageBlocksCount = 0;
@@ -341,6 +346,7 @@ class TIndexTabletState
     }
 
     TMiscNodeStats GetMiscNodeStats() const;
+    THandlesStats GetHandlesStats() const;
 
     const NProto::TFileStorePerformanceProfile& GetPerformanceProfile() const;
 

cloud/filestore/libs/storage/tablet/tablet_state_impl.h

@@ -48,6 +48,8 @@ struct TIndexTabletState::TImpl
 
     TNodeToSessionStat NodeToSessionStat;
 
+    i64 UsedDirectHandlesCount = 0;
+
     TWriteRequestList WriteBatch;
 
     TRangeLocks RangeLocks;

cloud/filestore/libs/storage/tablet/tablet_state_sessions.cpp

@@ -690,6 +690,10 @@ TSessionHandle* TIndexTabletState::CreateHandle(
     db.WriteSessionHandle(proto);
     IncrementUsedHandlesCount(db);
 
+    if (HasFlag(proto.GetFlags(), NProto::TCreateHandleRequest::E_DIRECT)) {
+        ++Impl->UsedDirectHandlesCount;
+    }
+
     return CreateHandle(session, proto);
 }
 
@@ -703,6 +707,10 @@ void TIndexTabletState::DestroyHandle(
 
     DecrementUsedHandlesCount(db);
 
+    if (HasFlag(handle->GetFlags(), NProto::TCreateHandleRequest::E_DIRECT)) {
+        --Impl->UsedDirectHandlesCount;
+    }
+
     ReleaseLocks(db, handle->GetHandle());
 
     Impl->ReadAheadCache.OnDestroyHandle(

cloud/filestore/libs/storage/tablet/tablet_ut_counters.cpp

@@ -882,6 +882,86 @@ Y_UNIT_TEST_SUITE(TIndexTabletTest_Counters)
              }},
         });
     }
+
+    Y_UNIT_TEST(ShouldReportDirectHandleMetrics)
+    {
+        TTestEnv env;
+        auto registry = env.GetRegistry();
+
+        env.CreateSubDomain("nfs");
+        ui32 nodeIdx = env.CreateNode("nfs");
+        ui64 tabletId = env.BootIndexTablet(nodeIdx);
+
+        TIndexTabletClient tablet(env.GetRuntime(), nodeIdx, tabletId);
+        tablet.InitSession("client", "session");
+
+        const auto nodeId =
+            CreateNode(tablet, TCreateNodeArgs::File(RootNodeId, "test"));
+
+        auto advanceTime = [&]()
+        {
+            env.GetRuntime().AdvanceCurrentTime(TDuration::Seconds(15));
+            NActors::TDispatchOptions options;
+            options.FinalEvents.emplace_back(
+                TEvIndexTabletPrivate::EvUpdateCounters);
+            env.GetRuntime().DispatchEvents(options);
+        };
+
+        auto checkHandlesCounters =
+            [&](i64 expectedDirectHandles, i64 expectedUsedHandles)
+        {
+            TTestRegistryVisitor visitor;
+            registry->Visit(TInstant::Zero(), visitor);
+            visitor.ValidateExpectedCounters({
+                {{{"sensor", "UsedDirectHandlesCount"}, {"filesystem", "test"}},
+                 expectedDirectHandles},
+                {{{"sensor", "UsedHandlesCount"}, {"filesystem", "test"}},
+                 expectedUsedHandles},
+            });
+        };
+
+        advanceTime();
+        checkHandlesCounters(0, 0);
+
+        const auto handleWithoutDirect =
+            CreateHandle(tablet, nodeId, {}, TCreateHandleArgs::RDWR);
+
+        advanceTime();
+        checkHandlesCounters(0, 1);
+
+        const auto handleWithDirect = CreateHandle(
+            tablet,
+            nodeId,
+            {},
+            TCreateHandleArgs::RDWR | TCreateHandleArgs::DIRECT);
+
+        advanceTime();
+        checkHandlesCounters(1, 2);
+
+        const auto anotherDirectHandle = CreateHandle(
+            tablet,
+            nodeId,
+            {},
+            TCreateHandleArgs::RDWR | TCreateHandleArgs::DIRECT);
+
+        advanceTime();
+        checkHandlesCounters(2, 3);
+
+        tablet.DestroyHandle(handleWithoutDirect);
+
+        advanceTime();
+        checkHandlesCounters(2, 2);
+
+        tablet.DestroyHandle(handleWithDirect);
+
+        advanceTime();
+        checkHandlesCounters(1, 1);
+
+        tablet.DestroyHandle(anotherDirectHandle);
+
+        advanceTime();
+        checkHandlesCounters(0, 0);
+    }
 }
 
 }   // namespace NCloud::NFileStore::NStorage

cloud/filestore/libs/storage/testlib/helpers.h

@@ -254,6 +254,9 @@ struct TCreateHandleArgs
 
     static constexpr ui32 TRUNC
         = ProtoFlag(NProto::TCreateHandleRequest::E_TRUNCATE);
+    
+    static constexpr ui32 DIRECT
+        = ProtoFlag(NProto::TCreateHandleRequest::E_DIRECT);
 };
 
 ////////////////////////////////////////////////////////////////////////////////