KIKIMR-19213: remove useless optimization

3 files changed, 20 insertions, 21 deletions

diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/plain_read_data.cpp b/ydb/core/tx/columnshard/engines/reader/plain_reader/plain_read_data.cpp
index a5f3ff41468..88f71ad9cb9 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/plain_read_data.cpp
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/plain_read_data.cpp
@@ -39,7 +39,7 @@ TPlainReadData::TPlainReadData(TReadMetadata::TConstPtr readMetadata, const TRea
             auto start = GetReadMetadata()->BuildSortedPosition((*itPortion)->IndexKeyStart());
             auto finish = GetReadMetadata()->BuildSortedPosition((*itPortion)->IndexKeyEnd());
             AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("event", "portions_for_merge")("start", start.DebugJson())("finish", finish.DebugJson());
-            sources.emplace_back(std::make_shared<TPortionDataSource>(sourceIdx++, (*itPortion), *this, start, finish));
+            sources.emplace_back(std::make_shared<TPortionDataSource>(sourceIdx++, *itPortion, *this, start, finish));
             ++itPortion;
         } else {
             auto start = GetReadMetadata()->BuildSortedPosition(itCommitted->GetFirstVerified());
diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/scanner.cpp b/ydb/core/tx/columnshard/engines/reader/plain_reader/scanner.cpp
index 307c5ff86a4..91d4574890e 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/scanner.cpp
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/scanner.cpp
@@ -27,13 +27,14 @@ TScanHead::TScanHead(std::deque<std::shared_ptr<IDataSource>>&& sources, TPlainR
 
 bool TScanHead::BuildNextInterval() {
     while (BorderPoints.size()) {
-        Y_VERIFY(FrontEnds.size());
+//        Y_VERIFY(FrontEnds.size());
         auto position = BorderPoints.begin()->first;
         auto firstBorderPointInfo = std::move(BorderPoints.begin()->second);
         const bool isIncludeStart = CurrentSegments.empty();
 
         for (auto&& i : firstBorderPointInfo.GetStartSources()) {
-            CurrentSegments.emplace(i->GetSourceIdx(), i);
+            AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("add_source", i->GetSourceIdx());
+            AFL_VERIFY(CurrentSegments.emplace(i->GetSourceIdx(), i).second)("idx", i->GetSourceIdx());
         }
 
         if (firstBorderPointInfo.GetStartSources().size() && firstBorderPointInfo.GetFinishSources().size()) {
@@ -44,20 +45,21 @@ bool TScanHead::BuildNextInterval() {
         }
 
         for (auto&& i : firstBorderPointInfo.GetFinishSources()) {
-            Y_VERIFY(CurrentSegments.erase(i->GetSourceIdx()));
+            AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("remove_source", i->GetSourceIdx());
+            AFL_VERIFY(CurrentSegments.erase(i->GetSourceIdx()))("idx", i->GetSourceIdx());
         }
 
-        const bool isFirstFinished = (position == *FrontEnds.begin());
-        if (firstBorderPointInfo.GetFinishSources().size()) {
-            Y_VERIFY(isFirstFinished);
-            Y_VERIFY(FrontEnds.erase(position));
-        } else {
-            Y_VERIFY(!FrontEnds.erase(position));
-        }
-
-        if (isFirstFinished) {
-            DrainSources();
-        }
+//        const bool isFirstFinished = (position == *FrontEnds.begin());
+//        if (firstBorderPointInfo.GetFinishSources().size()) {
+//            Y_VERIFY(isFirstFinished);
+//            Y_VERIFY(FrontEnds.erase(position));
+//        } else {
+//            Y_VERIFY(!FrontEnds.erase(position));
+//        }
+
+//        if (isFirstFinished) {
+//            DrainSources();
+//        }
         CurrentStart = BorderPoints.begin()->first;
         BorderPoints.erase(BorderPoints.begin());
         if (CurrentSegments.size()) {
@@ -85,12 +87,9 @@ void TScanHead::DrainResults() {
 }
 
 void TScanHead::DrainSources() {
-    if (Sources.empty()) {
-        return;
-    }
-    while (Sources.size() && (FrontEnds.empty() || Sources.front()->GetStart().Compare(*FrontEnds.begin()) != std::partial_ordering::greater)) {
+    while (Sources.size()/* && (FrontEnds.empty() || Sources.front()->GetStart().Compare(*FrontEnds.begin()) != std::partial_ordering::greater)*/) {
         auto source = Sources.front();
-        FrontEnds.emplace(source->GetFinish());
+//        FrontEnds.emplace(source->GetFinish());
         BorderPoints[source->GetStart()].AddStart(source);
         BorderPoints[source->GetFinish()].AddFinish(source);
         Sources.pop_front();
diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/scanner.h b/ydb/core/tx/columnshard/engines/reader/plain_reader/scanner.h
index f20df47faac..9c0525252ab 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/scanner.h
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/scanner.h
@@ -26,7 +26,7 @@ private:
     std::deque<std::shared_ptr<IDataSource>> Sources;
     std::vector<std::shared_ptr<arrow::Field>> ResultFields;
     THashMap<ui32, std::shared_ptr<IDataSource>> SourceByIdx;
-    std::set<NIndexedReader::TSortableBatchPosition> FrontEnds;
+//    std::set<NIndexedReader::TSortableBatchPosition> FrontEnds;
     std::map<NIndexedReader::TSortableBatchPosition, TDataSourceEndpoint> BorderPoints;
     std::map<ui32, std::shared_ptr<IDataSource>> CurrentSegments;
     std::optional<NIndexedReader::TSortableBatchPosition> CurrentStart;