diff --git a/ydb/core/protos/config.proto b/ydb/core/protos/config.proto
index 5db4d3087755..8cb9cf5442a4 100644
--- a/ydb/core/protos/config.proto
+++ b/ydb/core/protos/config.proto
@@ -1516,6 +1516,7 @@ message TColumnShardConfig {
 
     optional TIndexMetadataMemoryLimit IndexMetadataMemoryLimit = 12;
     optional bool CleanupEnabled = 13 [default = true];
+    optional uint32 MaxInFlightIntervalsOnRequest = 16;
 }
 
 message TSchemeShardConfig {
diff --git a/ydb/core/tx/columnshard/background_controller.h b/ydb/core/tx/columnshard/background_controller.h
index b88e1be3bcea..bb38f2744061 100644
--- a/ydb/core/tx/columnshard/background_controller.h
+++ b/ydb/core/tx/columnshard/background_controller.h
@@ -17,6 +17,7 @@ class TBackgroundController {
 
     bool ActiveCleanupPortions = false;
     bool ActiveCleanupTables = false;
+    bool ActiveCleanupInsertTable = false;
     YDB_READONLY(TMonotonic, LastIndexationInstant, TMonotonic::Zero());
 public:
     THashSet<NOlap::TPortionAddress> GetConflictTTLPortions() const;
@@ -66,6 +67,18 @@ class TBackgroundController {
     bool IsCleanupTablesActive() const {
         return ActiveCleanupTables;
     }
+
+    void StartCleanupInsertTable() {
+        Y_ABORT_UNLESS(!ActiveCleanupInsertTable);
+        ActiveCleanupInsertTable = true;
+    }
+    void FinishCleanupInsertTable() {
+        Y_ABORT_UNLESS(ActiveCleanupInsertTable);
+        ActiveCleanupInsertTable = false;
+    }
+    bool IsCleanupInsertTableActive() const {
+        return ActiveCleanupInsertTable;
+    }
 };
 
 }
diff --git a/ydb/core/tx/columnshard/blobs_action/abstract/blob_set.h b/ydb/core/tx/columnshard/blobs_action/abstract/blob_set.h
index 7692dad22eb2..756f0edb0a6f 100644
--- a/ydb/core/tx/columnshard/blobs_action/abstract/blob_set.h
+++ b/ydb/core/tx/columnshard/blobs_action/abstract/blob_set.h
@@ -89,7 +89,18 @@ class TTabletsByBlob {
     bool IsEmpty() const {
         return Data.empty();
     }
-
+    using TGenStep = std::tuple<ui32, ui32>;
+    std::deque<TUnifiedBlobId> GroupByGenStep() const {
+        std::deque<TUnifiedBlobId> result;
+        for (const auto& i : Data) {
+            result.emplace_back(i.first);
+        }
+        const auto pred = [](const TUnifiedBlobId& l, const TUnifiedBlobId& r) {
+            return TGenStep(l.GetLogoBlobId().Generation(), l.GetLogoBlobId().Step()) < TGenStep(r.GetLogoBlobId().Generation(), r.GetLogoBlobId().Step());
+        };
+        std::sort(result.begin(), result.end(), pred);
+        return result;
+    }
     template <class TFilter>
     TTabletsByBlob ExtractBlobs(const TFilter& filter, const std::optional<ui32> countLimit = {}) {
         TTabletsByBlob result;
diff --git a/ydb/core/tx/columnshard/blobs_action/bs/blob_manager.cpp b/ydb/core/tx/columnshard/blobs_action/bs/blob_manager.cpp
index ed3810ae1edf..84fe2768d5fd 100644
--- a/ydb/core/tx/columnshard/blobs_action/bs/blob_manager.cpp
+++ b/ydb/core/tx/columnshard/blobs_action/bs/blob_manager.cpp
@@ -211,7 +211,7 @@ std::vector<TGenStep> TBlobManager::FindNewGCBarriers() {
     return result;
 }
 
-std::shared_ptr<NBlobOperations::NBlobStorage::TGCTask> TBlobManager::BuildGCTask(const TString& storageId, 
+std::shared_ptr<NBlobOperations::NBlobStorage::TGCTask> TBlobManager::BuildGCTask(const TString& storageId,
     const std::shared_ptr<TBlobManager>& manager, const std::shared_ptr<NDataSharing::TStorageSharedBlobsManager>& sharedBlobsInfo,
     const std::shared_ptr<NBlobOperations::TRemoveGCCounters>& counters) noexcept {
     AFL_VERIFY(!CollectGenStepInFlight);
@@ -244,7 +244,7 @@ std::shared_ptr<NBlobOperations::NBlobStorage::TGCTask> TBlobManager::BuildGCTas
         }
     }
 
-    static const ui32 blobsGCCountLimit = 50000;
+    static const ui32 blobsGCCountLimit = 500000;
 
     const auto predShared = [&](const TUnifiedBlobId& id, const THashSet<TTabletId>& /*tabletIds*/) {
         return id.GetLogoBlobId().TabletID() != (ui64)SelfTabletId;
@@ -262,9 +262,8 @@ std::shared_ptr<NBlobOperations::NBlobStorage::TGCTask> TBlobManager::BuildGCTas
 
         TTabletsByBlob extractedOld = BlobsToDelete.ExtractBlobs(predRemoveOld, blobsGCCountLimit - extractedToRemoveFromDB.GetSize());
         extractedToRemoveFromDB.Add(extractedOld);
-        TTabletId tabletId;
-        TUnifiedBlobId unifiedBlobId;
-        while (extractedOld.ExtractFront(tabletId, unifiedBlobId)) {
+        for (TTabletsByBlob::TIterator itExtractedOld(extractedOld); itExtractedOld.IsValid(); ++itExtractedOld) {
+            const TUnifiedBlobId unifiedBlobId = itExtractedOld.GetBlobId();
             auto logoBlobId = unifiedBlobId.GetLogoBlobId();
             AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("to_delete_gc", logoBlobId);
             NBlobOperations::NBlobStorage::TGCTask::TGCLists& gl = perGroupGCListsInFlight[unifiedBlobId.GetDsGroup()];
@@ -278,6 +277,10 @@ std::shared_ptr<NBlobOperations::NBlobStorage::TGCTask> TBlobManager::BuildGCTas
 
 
     std::deque<TUnifiedBlobId> keepsToErase;
+    std::deque<TUnifiedBlobId> deleteIndex;
+    if (extractedToRemoveFromDB.GetSize() + keepsToErase.size() < blobsGCCountLimit) {
+        deleteIndex = BlobsToDelete.GroupByGenStep();
+    }
     for (auto&& newCollectGenStep : newCollectGenSteps) {
         AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("event", "PreparePerGroupGCRequests")("gen", std::get<0>(newCollectGenStep))("step", std::get<1>(newCollectGenStep));
         BlobsManagerCounters.OnNewCollectStep(std::get<0>(newCollectGenStep), std::get<1>(newCollectGenStep));
@@ -297,20 +300,38 @@ std::shared_ptr<NBlobOperations::NBlobStorage::TGCTask> TBlobManager::BuildGCTas
                 perGroupGCListsInFlight[blobGroup].KeepList.insert(*keepBlobIt);
                 keepsToErase.emplace_back(TUnifiedBlobId(blobGroup, *keepBlobIt));
                 AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("to_keep_gc", *keepBlobIt);
+                if (extractedToRemoveFromDB.GetSize() + keepsToErase.size() > blobsGCCountLimit) {
+                    AFL_WARN(NKikimrServices::TX_COLUMNSHARD)("event", "a lot of blobs to gc")("to_remove", extractedToRemoveFromDB.GetSize())("keeps_to_erase", keepsToErase.size())("limit", blobsGCCountLimit);
+                    break;
+                }
+            }
+            if (extractedToRemoveFromDB.GetSize() + keepsToErase.size() > blobsGCCountLimit) {
+                AFL_WARN(NKikimrServices::TX_COLUMNSHARD)("event", "a lot of blobs to gc")("to_remove", extractedToRemoveFromDB.GetSize())("keeps_to_erase", keepsToErase.size())("limit", blobsGCCountLimit);
+                break;
             }
             BlobsToKeep.erase(BlobsToKeep.begin(), keepBlobIt);
             BlobsManagerCounters.OnBlobsKeep(BlobsToKeep);
 
-            const auto predSelf = [&](const TUnifiedBlobId& id, const THashSet<TTabletId>& /*tabletIds*/) {
-                auto logoBlobId = id.GetLogoBlobId();
-                TGenStep genStep{logoBlobId.Generation(), logoBlobId.Step()};
-                return genStep <= newCollectGenStep && id.GetLogoBlobId().TabletID() == (ui64)SelfTabletId;
-            };
-            TTabletsByBlob extractedSelf = BlobsToDelete.ExtractBlobs(predSelf);
+            TTabletsByBlob extractedSelf;
+            {
+                while (deleteIndex.size()) {
+                    const auto& blobId = deleteIndex.front().GetLogoBlobId();
+                    if (newCollectGenStep < TGenStep(blobId.Generation(), blobId.Step())) {
+                        break;
+                    }
+                    BlobsToDelete.ExtractBlobTo(deleteIndex.front(), extractedSelf);
+                    if (extractedToRemoveFromDB.GetSize() + extractedSelf.GetSize() + keepsToErase.size() > blobsGCCountLimit) {
+                        AFL_WARN(NKikimrServices::TX_COLUMNSHARD)("event", "a lot of blobs to gc")("to_remove", extractedToRemoveFromDB.GetSize())("keeps_to_erase", keepsToErase.size())("limit", blobsGCCountLimit);
+                        break;
+                    }
+                    deleteIndex.pop_front();
+                }
+
+            }
+
             extractedToRemoveFromDB.Add(extractedSelf);
-            TTabletId tabletId;
-            TUnifiedBlobId unifiedBlobId;
-            while (extractedSelf.ExtractFront(tabletId, unifiedBlobId)) {
+            for (TTabletsByBlob::TIterator itExtractedSelf(extractedSelf); itExtractedSelf.IsValid(); ++itExtractedSelf) {
+                const TUnifiedBlobId unifiedBlobId = itExtractedSelf.GetBlobId();
                 auto logoBlobId = unifiedBlobId.GetLogoBlobId();
                 AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("to_delete_gc", logoBlobId);
                 NBlobOperations::NBlobStorage::TGCTask::TGCLists& gl = perGroupGCListsInFlight[unifiedBlobId.GetDsGroup()];
@@ -359,6 +380,8 @@ std::shared_ptr<NBlobOperations::NBlobStorage::TGCTask> TBlobManager::BuildGCTas
     return result;
 }
 
+
+
 TBlobBatch TBlobManager::StartBlobBatch(ui32 channel) {
     ++CountersUpdate.BatchesStarted;
     Y_ABORT_UNLESS(channel == BLOB_CHANNEL, "Support for mutiple blob channels is not implemented yet");
diff --git a/ydb/core/tx/columnshard/blobs_action/transaction/tx_gc_insert_table.cpp b/ydb/core/tx/columnshard/blobs_action/transaction/tx_gc_insert_table.cpp
index ece65128719a..15a05e7108a7 100644
--- a/ydb/core/tx/columnshard/blobs_action/transaction/tx_gc_insert_table.cpp
+++ b/ydb/core/tx/columnshard/blobs_action/transaction/tx_gc_insert_table.cpp
@@ -30,7 +30,8 @@ void TTxInsertTableCleanup::Complete(const TActorContext& /*ctx*/) {
 
     Y_ABORT_UNLESS(BlobsAction);
     BlobsAction->OnCompleteTxAfterRemoving(true);
-    Self->EnqueueBackgroundActivities();
+    Self->BackgroundController.FinishCleanupInsertTable();
+    Self->SetupCleanupInsertTable();
 }
 
 }
diff --git a/ydb/core/tx/columnshard/columnshard_impl.cpp b/ydb/core/tx/columnshard/columnshard_impl.cpp
index dd7aaf540533..64b33bb519f1 100644
--- a/ydb/core/tx/columnshard/columnshard_impl.cpp
+++ b/ydb/core/tx/columnshard/columnshard_impl.cpp
@@ -845,6 +845,10 @@ void TColumnShard::Handle(TEvPrivate::TEvGarbageCollectionFinished::TPtr& ev, co
 }
 
 void TColumnShard::SetupCleanupInsertTable() {
+    if (BackgroundController.IsCleanupInsertTableActive()) {
+        ACFL_DEBUG("background", "cleanup_insert_table")("skip_reason", "in_progress");
+        return;
+    }
     auto writeIdsToCleanup = InsertTable->OldWritesToAbort(AppData()->TimeProvider->Now());
 
     if (!InsertTable->GetAborted().size() && !writeIdsToCleanup.size()) {
@@ -852,6 +856,7 @@ void TColumnShard::SetupCleanupInsertTable() {
     }
     AFL_INFO(NKikimrServices::TX_COLUMNSHARD)("event", "cleanup_started")("aborted", InsertTable->GetAborted().size())("to_cleanup", writeIdsToCleanup.size());
 
+    BackgroundController.StartCleanupInsertTable();
     Execute(new TTxInsertTableCleanup(this, std::move(writeIdsToCleanup)), TActorContext::AsActorContext());
 }
 
diff --git a/ydb/core/tx/columnshard/engines/column_engine.cpp b/ydb/core/tx/columnshard/engines/column_engine.cpp
index d6f46742093c..288be294731e 100644
--- a/ydb/core/tx/columnshard/engines/column_engine.cpp
+++ b/ydb/core/tx/columnshard/engines/column_engine.cpp
@@ -9,15 +9,16 @@ const std::shared_ptr<arrow::Schema>& IColumnEngine::GetReplaceKey() const {
 }
 
 ui64 IColumnEngine::GetMetadataLimit() {
+    static const auto MemoryTotal = NSystemInfo::TotalMemorySize();
     if (!HasAppData()) {
-        AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("total", NSystemInfo::TotalMemorySize());
-        return NSystemInfo::TotalMemorySize() * 0.3;
+        AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("total", MemoryTotal);
+        return MemoryTotal * 0.3;
     } else if (AppDataVerified().ColumnShardConfig.GetIndexMetadataMemoryLimit().HasAbsoluteValue()) {
         AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("value", AppDataVerified().ColumnShardConfig.GetIndexMetadataMemoryLimit().GetAbsoluteValue());
         return AppDataVerified().ColumnShardConfig.GetIndexMetadataMemoryLimit().GetAbsoluteValue();
     } else {
-        AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("total", NSystemInfo::TotalMemorySize())("kff", AppDataVerified().ColumnShardConfig.GetIndexMetadataMemoryLimit().GetTotalRatio());
-        return NSystemInfo::TotalMemorySize() * AppDataVerified().ColumnShardConfig.GetIndexMetadataMemoryLimit().GetTotalRatio();
+        AFL_DEBUG(NKikimrServices::TX_COLUMNSHARD)("total", MemoryTotal)("kff", AppDataVerified().ColumnShardConfig.GetIndexMetadataMemoryLimit().GetTotalRatio());
+        return MemoryTotal * AppDataVerified().ColumnShardConfig.GetIndexMetadataMemoryLimit().GetTotalRatio();
     }
 }
 
diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/scanner.cpp b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/scanner.cpp
index f0c789f3d205..8442648344b7 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/scanner.cpp
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/scanner.cpp
@@ -9,7 +9,7 @@ void TScanHead::OnIntervalResult(const std::optional<NArrow::TShardedRecordBatch
     std::unique_ptr<NArrow::NMerger::TMergePartialStream>&& merger, const ui32 intervalIdx, TPlainReadData& reader) {
     if (Context->GetReadMetadata()->Limit && (!newBatch || newBatch->GetRecordsCount() == 0) && InFlightLimit < 1000) {
         if (++ZeroCount == std::max<ui64>(16, InFlightLimit)) {
-            InFlightLimit *= 2;
+            InFlightLimit = std::max<ui32>(MaxInFlight, InFlightLimit * 2);
             ZeroCount = 0;
         }
     } else {
@@ -96,7 +96,17 @@ TConclusionStatus TScanHead::Start() {
 TScanHead::TScanHead(std::deque<std::shared_ptr<IDataSource>>&& sources, const std::shared_ptr<TSpecialReadContext>& context)
     : Context(context)
 {
-    InFlightLimit = Context->GetReadMetadata()->Limit ? 1 : Max<ui32>();
+    if (!HasAppData() || !AppDataVerified().ColumnShardConfig.HasMaxInFlightIntervalsOnRequest()) {
+        MaxInFlight = 256;
+    } else {
+        MaxInFlight = AppDataVerified().ColumnShardConfig.GetMaxInFlightIntervalsOnRequest();
+    }
+
+    if (Context->GetReadMetadata()->Limit) {
+        InFlightLimit = 1;
+    } else {
+        InFlightLimit = MaxInFlight;
+    }
     while (sources.size()) {
         auto source = sources.front();
         BorderPoints[source->GetStart()].AddStart(source);
diff --git a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/scanner.h b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/scanner.h
index 75de439aec63..7092dac19acd 100644
--- a/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/scanner.h
+++ b/ydb/core/tx/columnshard/engines/reader/plain_reader/iterator/scanner.h
@@ -78,6 +78,7 @@ class TScanHead {
     ui32 SegmentIdxCounter = 0;
     std::vector<TIntervalStat> IntervalStats;
     ui64 InFlightLimit = 1;
+    ui64 MaxInFlight = 256;
     ui64 ZeroCount = 0;
     bool AbortFlag = false;
     void DrainSources();