Sensor for number of shards within single BulkUpsert data (#11786)

Author: fexolm

ydb/core/tx/data_events/shard_writer.h

@@ -39,6 +39,7 @@ class TCSUploadCounters: public NColumnShard::TCommonCountersOwner {
     NMonitoring::THistogramPtr FailedFullReplyDuration;
     NMonitoring::THistogramPtr BytesDistribution;
     NMonitoring::THistogramPtr RowsDistribution;
+    NMonitoring::THistogramPtr ShardsCountDistribution;
     NMonitoring::TDynamicCounters::TCounterPtr RowsCount;
     NMonitoring::TDynamicCounters::TCounterPtr BytesCount;
     NMonitoring::TDynamicCounters::TCounterPtr FailsCount;
@@ -54,6 +55,7 @@ class TCSUploadCounters: public NColumnShard::TCommonCountersOwner {
         , FailedFullReplyDuration(TBase::GetHistogram("Replies/Failed/Full/DurationMs", NMonitoring::ExponentialHistogram(15, 2, 10)))
         , BytesDistribution(TBase::GetHistogram("Requests/Bytes", NMonitoring::ExponentialHistogram(15, 2, 1024)))
         , RowsDistribution(TBase::GetHistogram("Requests/Rows", NMonitoring::ExponentialHistogram(15, 2, 16)))
+        , ShardsCountDistribution(TBase::GetHistogram("Requests/ShardSplits", NMonitoring::LinearHistogram(50, 1, 1)))
         , RowsCount(TBase::GetDeriviative("Rows"))
         , BytesCount(TBase::GetDeriviative("Bytes"))
         , FailsCount(TBase::GetDeriviative("Fails"))
@@ -81,6 +83,10 @@ class TCSUploadCounters: public NColumnShard::TCommonCountersOwner {
         FailsCount->Add(1);
     }
 
+    void OnSplitByShards(const ui64 shardsCount) const {
+        ShardsCountDistribution->Collect(shardsCount);
+    }
+
     void OnCSReply(const TDuration d) const {
         CSReplyDuration->Collect(d.MilliSeconds());
     }

ydb/core/tx/tx_proxy/rpc_long_tx.cpp

@@ -98,6 +98,8 @@ class TLongTxWriteBase: public TActorBootstrapped<TLongTxWriteImpl>,
         const auto& splittedData = shardsSplitter->GetSplitData();
         InternalController =
             std::make_shared<NEvWrite::TWritersController>(splittedData.GetShardRequestsCount(), this->SelfId(), LongTxId, NoTxWrite);
+
+        InternalController->GetCounters()->OnSplitByShards(splittedData.GetShardsCount());
         ui32 sumBytes = 0;
         ui32 rowsCount = 0;
         ui32 writeIdx = 0;