Add Fallback system counter

ref:52a552773546d0f8f6b60ace8cf0734b6bae229d

2 files changed, 11 insertions, 0 deletions

diff --git a/ydb/library/yql/core/facade/yql_facade.cpp b/ydb/library/yql/core/facade/yql_facade.cpp
index 77b71e69826..035975464f5 100644
--- a/ydb/library/yql/core/facade/yql_facade.cpp
+++ b/ydb/library/yql/core/facade/yql_facade.cpp
@@ -993,6 +993,7 @@ TFuture<IGraphTransformer::TStatus> TProgram::AsyncTransformWithFallback(bool ap
                 ExprCtx_->IssueManager.AddIssues({warning});
             }
 
+            FallbackCounter ++;
             // don't execute recapture again
             ExprCtx_->Step.Done(TExprStep::Recapture);
             return AsyncTransformWithFallback(false);
@@ -1162,6 +1163,15 @@ TMaybe<TString> TProgram::GetStatistics(bool totalOnly) {
             writer.OnKeyedItem("count");
             writer.OnInt64Scalar(rusage.MajorPageFaults);
         writer.OnEndMap();
+
+        if (FallbackCounter) {
+            writer.OnKeyedItem("Fallback");
+            writer.OnBeginMap();
+                writer.OnKeyedItem("count");
+                writer.OnInt64Scalar(FallbackCounter);
+            writer.OnEndMap();
+        }
+
     writer.OnEndMap(); // system
 
     // Footer
diff --git a/ydb/library/yql/core/facade/yql_facade.h b/ydb/library/yql/core/facade/yql_facade.h
index 586747551f1..4ba75c5ba78 100644
--- a/ydb/library/yql/core/facade/yql_facade.h
+++ b/ydb/library/yql/core/facade/yql_facade.h
@@ -386,6 +386,7 @@ private:
     TOperationProgressWriter ProgressWriter_ = [](const TOperationProgress&) {};
     TString ExtractedQueryParametersMetadataYson_;
     const bool EnableRangeComputeFor_;
+    i64 FallbackCounter = 0;
 };
 
 } // namspace NYql