diff --git a/ydb/core/tx/columnshard/engines/changes/general_compaction.cpp b/ydb/core/tx/columnshard/engines/changes/general_compaction.cpp
index 5d866ae4e32e..ff67fcbba702 100644
--- a/ydb/core/tx/columnshard/engines/changes/general_compaction.cpp
+++ b/ydb/core/tx/columnshard/engines/changes/general_compaction.cpp
@@ -266,4 +266,12 @@ void TGeneralCompactColumnEngineChanges::AddCheckPoint(const NIndexedReader::TSo
     AFL_VERIFY(CheckPoints.emplace(position, include).second || !validationDuplications);
 }
 
+std::shared_ptr<TGeneralCompactColumnEngineChanges::IMemoryPredictor> TGeneralCompactColumnEngineChanges::BuildMemoryPredictor() {
+    if (!HasAppData() || AppDataVerified().ColumnShardConfig.GetUseChunkedMergeOnCompaction()) {
+        return std::make_shared<TMemoryPredictorChunkedPolicy>();
+    } else {
+        return std::make_shared<TMemoryPredictorSimplePolicy>();
+    }
+}
+
 }
diff --git a/ydb/core/tx/columnshard/engines/changes/general_compaction.h b/ydb/core/tx/columnshard/engines/changes/general_compaction.h
index 811eab38aa60..506966ac3494 100644
--- a/ydb/core/tx/columnshard/engines/changes/general_compaction.h
+++ b/ydb/core/tx/columnshard/engines/changes/general_compaction.h
@@ -19,15 +19,62 @@ class TGeneralCompactColumnEngineChanges: public TCompactColumnEngineChanges {
     virtual void DoStart(NColumnShard::TColumnShard& self) override;
     virtual NColumnShard::ECumulativeCounters GetCounterIndex(const bool isSuccess) const override;
     virtual ui64 DoCalcMemoryForUsage() const override {
+        auto predictor = BuildMemoryPredictor();
         ui64 result = 0;
         for (auto& p : SwitchedPortions) {
-            result += 2 * p.GetBlobBytes();
+            result = predictor->AddPortion(p);
         }
         return result;
     }
 public:
     using TBase::TBase;
 
+    class IMemoryPredictor {
+    public:
+        virtual ui64 AddPortion(const TPortionInfo& portionInfo) = 0;
+        virtual ~IMemoryPredictor() = default;
+    };
+
+    class TMemoryPredictorSimplePolicy: public IMemoryPredictor {
+    private:
+        ui64 SumMemory = 0;
+    public:
+        virtual ui64 AddPortion(const TPortionInfo& portionInfo) override {
+            for (auto&& i : portionInfo.GetRecords()) {
+                SumMemory += i.BlobRange.Size;
+                SumMemory += 2 * i.GetMeta().GetRawBytesVerified();
+            }
+            return SumMemory;
+        }
+    };
+
+    class TMemoryPredictorChunkedPolicy: public IMemoryPredictor {
+    private:
+        ui64 SumMemory = 0;
+        ui32 PortionsCount = 0;
+        THashMap<ui32, ui64> MaxMemoryByColumnChunk;
+    public:
+        virtual ui64 AddPortion(const TPortionInfo& portionInfo) override {
+            SumMemory += portionInfo.GetRecordsCount() * (2 * sizeof(ui64) + sizeof(ui32) + sizeof(ui16));
+            for (auto&& i : portionInfo.GetRecords()) {
+                SumMemory += i.BlobRange.Size;
+                auto it = MaxMemoryByColumnChunk.find(i.GetColumnId());
+                ++PortionsCount;
+                if (it == MaxMemoryByColumnChunk.end()) {
+                    it = MaxMemoryByColumnChunk.emplace(i.GetColumnId(), i.GetMeta().GetRawBytesVerified()).first;
+                    SumMemory += it->second * PortionsCount;
+                } else if (it->second < i.GetMeta().GetRawBytesVerified()) {
+                    SumMemory -= it->second * (PortionsCount - 1);
+                    it->second = i.GetMeta().GetRawBytesVerified();
+                    SumMemory += it->second * PortionsCount;
+                }
+            }
+            return SumMemory;
+        }
+    };
+
+    static std::shared_ptr<IMemoryPredictor> BuildMemoryPredictor();
+
     void AddCheckPoint(const NIndexedReader::TSortableBatchPosition& position, const bool include = true, const bool validationDuplications = true);
 
     virtual TString TypeString() const override {
diff --git a/ydb/core/tx/columnshard/engines/portions/portion_info.h b/ydb/core/tx/columnshard/engines/portions/portion_info.h
index 2ba089bb80d9..b182e74dbf5a 100644
--- a/ydb/core/tx/columnshard/engines/portions/portion_info.h
+++ b/ydb/core/tx/columnshard/engines/portions/portion_info.h
@@ -25,6 +25,12 @@ class TPortionInfo {
     std::shared_ptr<NOlap::IBlobsStorageOperator> BlobsOperator;
     ui64 DeprecatedGranuleId = 0;
 public:
+    std::vector<TColumnRecord> Records;
+
+    const std::vector<TColumnRecord>& GetRecords() const {
+        return Records;
+    }
+
     ui64 GetPathId() const {
         return PathId;
     }
@@ -117,8 +123,6 @@ class TPortionInfo {
         return Meta;
     }
 
-    std::vector<TColumnRecord> Records;
-
     const TColumnRecord* GetRecordPointer(const TChunkAddress& address) const {
         for (auto&& i : Records) {
             if (i.GetAddress() == address) {
diff --git a/ydb/core/tx/columnshard/engines/storage/optimizer/lbuckets/optimizer.h b/ydb/core/tx/columnshard/engines/storage/optimizer/lbuckets/optimizer.h
index 8ebfc8681af8..531279ccd244 100644
--- a/ydb/core/tx/columnshard/engines/storage/optimizer/lbuckets/optimizer.h
+++ b/ydb/core/tx/columnshard/engines/storage/optimizer/lbuckets/optimizer.h
@@ -360,13 +360,12 @@ class TPortionsPool {
         std::sort(sorted.begin(), sorted.end(), pred);
 
         std::vector<std::shared_ptr<TPortionInfo>> result;
-        ui64 currentSize = 0;
+        std::shared_ptr<NCompaction::TGeneralCompactColumnEngineChanges::IMemoryPredictor> predictor = NCompaction::TGeneralCompactColumnEngineChanges::BuildMemoryPredictor();
         for (auto&& i : sorted) {
-            if (currentSize > sizeLimit && result.size() > 1) {
+            result.emplace_back(i);
+            if (predictor->AddPortion(*i) > sizeLimit && result.size() > 1) {
                 break;
             }
-            result.emplace_back(i);
-            currentSize += i->GetBlobBytes();
         }
         if (result.size() < sorted.size()) {
             separatePoint = sorted[result.size()]->IndexKeyStart();