diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/columns_set.h b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/columns_set.h
index 23514aff1dce..a0a3df00d04b 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/columns_set.h
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/columns_set.h
@@ -15,9 +15,10 @@ enum class EMemType {
 };
 
 enum class EStageFeaturesIndexes {
-    Filter = 0,
-    Fetching = 1,
-    Merge = 2
+    Accessors = 0,
+    Filter = 1,
+    Fetching = 2,
+    Merge = 3
 };
 
 class TIndexesSet {
diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/context.cpp b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/context.cpp
index 28d31123ebaf..5e7be055cbc7 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/context.cpp
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/context.cpp
@@ -27,7 +27,10 @@ std::shared_ptr<TFetchingScript> TSpecialReadContext::GetColumnsFetchingPlan(con
     if (source->NeedAccessorsFetching()) {
         if (!AskAccumulatorsScript) {
             AskAccumulatorsScript = std::make_shared<TFetchingScript>(*this);
-            AskAccumulatorsScript->AddStep(std::make_shared<TPortionAccessorFetchingStep>());
+            if (ui64 size = source->PredictAccessorsMemory()) {
+                AskAccumulatorsScript->AddStep<TAllocateMemoryStep>(size, EStageFeaturesIndexes::Accessors);
+            }
+            AskAccumulatorsScript->AddStep<TPortionAccessorFetchingStep>();
         }
         AskAccumulatorsScript->AddStep<TDetectInMem>(*FFColumns);
         return AskAccumulatorsScript;
@@ -54,8 +57,8 @@ std::shared_ptr<TFetchingScript> TSpecialReadContext::GetColumnsFetchingPlan(con
         }
     }
     {
-        auto result = CacheFetchingScripts[needSnapshots ? 1 : 0][isWholeExclusiveSource ? 1 : 0][partialUsageByPK ? 1 : 0]
-                                                               [useIndexes ? 1 : 0][needShardingFilter ? 1 : 0][hasDeletions ? 1 : 0];
+        auto result = CacheFetchingScripts[needSnapshots ? 1 : 0][isWholeExclusiveSource ? 1 : 0][partialUsageByPK ? 1 : 0][useIndexes ? 1 : 0]
+                                          [needShardingFilter ? 1 : 0][hasDeletions ? 1 : 0];
         if (!result) {
             TGuard<TMutex> wg(Mutex);
             result = CacheFetchingScripts[needSnapshots ? 1 : 0][isWholeExclusiveSource ? 1 : 0][partialUsageByPK ? 1 : 0][useIndexes ? 1 : 0]
@@ -274,11 +277,11 @@ std::shared_ptr<TFetchingScript> TSpecialReadContext::BuildColumnsFetchingPlan(c
 
 TSpecialReadContext::TSpecialReadContext(const std::shared_ptr<TReadContext>& commonContext)
     : CommonContext(commonContext) {
-
     ReadMetadata = dynamic_pointer_cast<const TReadMetadata>(CommonContext->GetReadMetadata());
     Y_ABORT_UNLESS(ReadMetadata);
     Y_ABORT_UNLESS(ReadMetadata->SelectInfo);
 
+    double kffAccessors = 0.01;
     double kffFilter = 0.45;
     double kffFetching = 0.45;
     double kffMerge = 0.10;
@@ -287,15 +290,19 @@ TSpecialReadContext::TSpecialReadContext(const std::shared_ptr<TReadContext>& co
         stagePrefix = "EF";
         kffFilter = 0.7;
         kffFetching = 0.15;
-        kffMerge = 0.15;
+        kffMerge = 0.14;
+        kffAccessors = 0.01;
     } else {
         stagePrefix = "FO";
         kffFilter = 0.1;
         kffFetching = 0.75;
-        kffMerge = 0.15;
+        kffMerge = 0.14;
+        kffAccessors = 0.01;
     }
 
-    std::vector<std::shared_ptr<NGroupedMemoryManager::TStageFeatures>> stages = { 
+    std::vector<std::shared_ptr<NGroupedMemoryManager::TStageFeatures>> stages = {
+        NGroupedMemoryManager::TScanMemoryLimiterOperator::BuildStageFeatures(
+            stagePrefix + "::ACCESSORS", kffAccessors * TGlobalLimits::ScanMemoryLimit),
         NGroupedMemoryManager::TScanMemoryLimiterOperator::BuildStageFeatures(
             stagePrefix + "::FILTER", kffFilter * TGlobalLimits::ScanMemoryLimit),
         NGroupedMemoryManager::TScanMemoryLimiterOperator::BuildStageFeatures(
@@ -304,8 +311,8 @@ TSpecialReadContext::TSpecialReadContext(const std::shared_ptr<TReadContext>& co
     };
     ProcessMemoryGuard =
         NGroupedMemoryManager::TScanMemoryLimiterOperator::BuildProcessGuard(CommonContext->GetReadMetadata()->GetTxId(), stages);
-    ProcessScopeGuard =
-        NGroupedMemoryManager::TScanMemoryLimiterOperator::BuildScopeGuard(CommonContext->GetReadMetadata()->GetTxId(), GetCommonContext()->GetScanId());
+    ProcessScopeGuard = NGroupedMemoryManager::TScanMemoryLimiterOperator::BuildScopeGuard(
+        CommonContext->GetReadMetadata()->GetTxId(), GetCommonContext()->GetScanId());
 
     auto readSchema = ReadMetadata->GetResultSchema();
     SpecColumns = std::make_shared<TColumnsSet>(TIndexInfo::GetSnapshotColumnIdsSet(), readSchema);
diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/fetching.cpp b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/fetching.cpp
index f09e0e5b9a0a..fbeaba7f098b 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/fetching.cpp
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/fetching.cpp
@@ -200,7 +200,7 @@ void TAllocateMemoryStep::TFetchingStepAllocation::DoOnAllocationImpossible(cons
 TConclusion<bool> TAllocateMemoryStep::DoExecuteInplace(
     const std::shared_ptr<IDataSource>& source, const TFetchingScriptCursor& step) const {
 
-    ui64 size = 0;
+    ui64 size = PredefinedSize.value_or(0);
     for (auto&& i : Packs) {
         ui32 sizeLocal = source->GetColumnsVolume(i.GetColumns().GetColumnIds(), i.GetMemType());
         if (source->GetStageData().GetUseFilter() && source->GetContext()->GetReadMetadata()->Limit && i.GetMemType() != EMemType::Blob) {
diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/fetching.h b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/fetching.h
index f9e5774c4aba..f630c36ebae5 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/fetching.h
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/fetching.h
@@ -227,6 +227,7 @@ class TAllocateMemoryStep: public IFetchingStep {
     std::vector<TColumnsPack> Packs;
     THashMap<ui32, THashSet<EMemType>> Control;
     const EStageFeaturesIndexes StageIndex;
+    std::optional<ui64> PredefinedSize;
 
 protected:
     class TFetchingStepAllocation: public NGroupedMemoryManager::IAllocation {
@@ -238,6 +239,7 @@ class TAllocateMemoryStep: public IFetchingStep {
         virtual bool DoOnAllocated(std::shared_ptr<NGroupedMemoryManager::TAllocationGuard>&& guard,
             const std::shared_ptr<NGroupedMemoryManager::IAllocation>& allocation) override;
         virtual void DoOnAllocationImpossible(const TString& errorMessage) override;
+
     public:
         TFetchingStepAllocation(const std::shared_ptr<IDataSource>& source, const ui64 mem, const TFetchingScriptCursor& step);
     };
@@ -266,6 +268,12 @@ class TAllocateMemoryStep: public IFetchingStep {
         , StageIndex(stageIndex) {
         AddAllocation(columns, memType);
     }
+
+    TAllocateMemoryStep(const ui64 size, const EStageFeaturesIndexes stageIndex)
+        : TBase("ALLOCATE_MEMORY::" + ::ToString(stageIndex))
+        , StageIndex(stageIndex)
+        , PredefinedSize(size) {
+    }
 };
 
 class TDetectInMemStep: public IFetchingStep {
diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/source.h b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/source.h
index 563dab447720..fe164bd212b8 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/source.h
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/source.h
@@ -77,7 +77,7 @@ class IDataSource {
 public:
     virtual bool NeedAccessorsForRead() const = 0;
     virtual bool NeedAccessorsFetching() const = 0;
-
+    virtual ui64 PredictAccessorsMemory() const = 0;
     bool StartFetchingAccessor(const std::shared_ptr<IDataSource>& sourcePtr, const TFetchingScriptCursor& step) {
         return DoStartFetchingAccessor(sourcePtr, step);
     }
@@ -318,6 +318,10 @@ class TPortionDataSource: public IDataSource {
     virtual bool DoStartFetchingAccessor(const std::shared_ptr<IDataSource>& sourcePtr, const TFetchingScriptCursor& step) override;
 
 public:
+    virtual ui64 PredictAccessorsMemory() const override {
+        return Portion->GetApproxChunksCount(GetContext()->GetCommonContext()->GetReadMetadata()->GetResultSchema()->GetColumnsCount()) * sizeof(TColumnRecord);
+    }
+
     virtual bool NeedAccessorsForRead() const override {
         return true;
     }
@@ -430,6 +434,10 @@ class TCommittedDataSource: public IDataSource {
     }
 
 public:
+    virtual ui64 PredictAccessorsMemory() const override {
+        return 0;
+    }
+
     virtual bool NeedAccessorsForRead() const override {
         return false;
     }