Switch to TRope reply in TEvGet query result KIKIMR-18394

48 files changed, 205 insertions, 181 deletions

diff --git a/library/cpp/actors/util/rc_buf.h b/library/cpp/actors/util/rc_buf.h
index 60d0ef904a1..11a09f5b9ad 100644
--- a/library/cpp/actors/util/rc_buf.h
+++ b/library/cpp/actors/util/rc_buf.h
@@ -446,14 +446,12 @@ class TRcBuf {
             }
             return Visit(Owner, [](EType, auto& value) -> TContiguousSpan {
                 using T = std::decay_t<decltype(value)>;
-                if constexpr (std::is_same_v<T, TString>) {
-                    return {&(*value.cbegin()), value.size()};
-                } else if constexpr (std::is_same_v<T, NActors::TSharedData> || std::is_same_v<T, TInternalBackend>) {
+                if constexpr (std::is_same_v<T, TString> || std::is_same_v<T, NActors::TSharedData> || std::is_same_v<T, TInternalBackend>) {
                     return {value.data(), value.size()};
                 } else if constexpr (std::is_same_v<T, IContiguousChunk::TPtr>) {
                     return value->GetData();
                 } else {
-                    return {};
+                    static_assert(TDependentFalse<T>, "unexpected type");
                 }
             });
         }
@@ -479,7 +477,7 @@ class TRcBuf {
                 } else if constexpr (std::is_same_v<T, IContiguousChunk::TPtr>) {
                     return value->GetDataMut();
                 } else {
-                    return {};
+                    static_assert(TDependentFalse<T>, "unexpected type");
                 }
             });
         }
@@ -497,7 +495,7 @@ class TRcBuf {
                 } else if constexpr (std::is_same_v<T, IContiguousChunk::TPtr>) {
                     return value->UnsafeGetDataMut();
                 } else {
-                    return {};
+                    static_assert(TDependentFalse<T>, "unexpected type");
                 }
             });
         }
@@ -515,7 +513,7 @@ class TRcBuf {
                 } else if constexpr (std::is_same_v<T, IContiguousChunk::TPtr>) {
                     return value->GetOccupiedMemorySize();
                 } else {
-                    Y_FAIL();
+                    static_assert(TDependentFalse<T>, "unexpected type");
                 }
             });
         }
@@ -582,28 +580,26 @@ class TRcBuf {
             return false;
         }
 
-        template <class TResult>
-        TResult GetRaw() const {
+        template <typename TResult, typename TCallback>
+        std::invoke_result_t<TCallback, const TResult*> ApplySpecificValue(TCallback&& callback) const {
+            static_assert(std::is_same_v<TResult, TString> ||
+                std::is_same_v<TResult, NActors::TSharedData> ||
+                std::is_same_v<TResult, TInternalBackend> ||
+                std::is_same_v<TResult, IContiguousChunk::TPtr>);
+
             if (!Owner) {
-                return TResult{};
+                return callback(nullptr);
             }
-            return Visit(Owner, [](EType, auto& value) {
+            return Visit(Owner, [&](EType, auto& value) {
                 using T = std::decay_t<decltype(value)>;
                 if constexpr (std::is_same_v<T, TResult>) {
-                    return value;
+                    return callback(&value);
                 } else {
-                    Y_FAIL();
-                    return TResult{}; // unreachable
+                    return callback(nullptr);
                 }
             });
         }
 
-        NActors::TSharedData GetRawTrimmed(size_t size) const {
-            NActors::TSharedData result = GetRaw<NActors::TSharedData>();
-            result.TrimBack(size);
-            return result;
-        }
-
         explicit operator bool() const {
             return static_cast<bool>(Owner);
         }
@@ -845,28 +841,6 @@ public:
         return Backend.ContainsNativeType<TType>();
     }
 
-    template <class TResult>
-    TResult GetRaw() const {
-        return Backend.GetRaw<TResult>();
-    }
-
-    NActors::TSharedData GetRawTrimmed(size_t size) const {
-        return Backend.GetRawTrimmed(size);
-    }
-
-    bool ReferencesWholeContainer() const {
-        return Backend.GetData().size() == GetSize();
-    }
-
-
-    bool ReferencesTrimableToWholeContainer() const {
-        if (ContainsNativeType<NActors::TSharedData>()) {
-            return Backend.GetData().size() == (GetSize() + UnsafeTailroom());
-        } else {
-            return ReferencesWholeContainer();
-        }
-    }
-
     bool CanGrowFront() const noexcept {
         return Backend.CanGrowFront(Begin);
     }
@@ -913,18 +887,30 @@ public:
 
     template <class TResult>
     TResult ExtractUnderlyingContainerOrCopy() const {
-        if (ContainsNativeType<TResult>() && (ReferencesWholeContainer() || ReferencesTrimableToWholeContainer())) {
-            using T = std::decay_t<TResult>;
-            if constexpr (std::is_same_v<T, NActors::TSharedData>) {
-                return GetRawTrimmed(GetSize());
-            } else {
-                return GetRaw<TResult>();
+        static_assert(std::is_same_v<TResult, TString> ||
+            std::is_same_v<TResult, NActors::TSharedData> ||
+            std::is_same_v<TResult, TInternalBackend>);
+
+        constexpr bool isSharedData = std::is_same_v<TResult, NActors::TSharedData>;
+        TResult res;
+
+        const bool found = Backend.ApplySpecificValue<TResult>([&](const TResult *raw) {
+            if (raw && raw->data() == Begin && (isSharedData ? End <= Begin + raw->size() : End == Begin + raw->size())) {
+                if constexpr (isSharedData) {
+                    raw->TrimBack(size());
+                }
+                res = TResult(*raw);
+                return true;
             }
+            return false;
+        });
+
+        if (!found) {
+            res = TResult::Uninitialized(GetSize());
+            char* data = NContiguousDataDetails::TContainerTraits<TResult>::UnsafeGetDataMut(res);
+            std::memcpy(data, GetData(), GetSize());
         }
 
-        TResult res = TResult::Uninitialized(GetSize());
-        char* data = NContiguousDataDetails::TContainerTraits<TResult>::UnsafeGetDataMut(res);
-        std::memcpy(data, Begin, End - Begin);
         return res;
     }
 
@@ -932,7 +918,7 @@ public:
         return {GetData(), GetSize()};
     }
 
-    TStringBuf Slice(size_t pos = 0, size_t len = -1) const noexcept {
+    TStringBuf Slice(size_t pos = 0, size_t len = Max<size_t>()) const noexcept {
         pos = Min(pos, size());
         len = Min(len, size() - pos);
         return {const_cast<TRcBuf*>(this)->UnsafeGetDataMut() + pos, len};
diff --git a/library/cpp/actors/util/rope.h b/library/cpp/actors/util/rope.h
index 3c655881814..9df251db9ce 100644
--- a/library/cpp/actors/util/rope.h
+++ b/library/cpp/actors/util/rope.h
@@ -455,6 +455,10 @@ public:
         return !Size;
     }
 
+    bool empty() const {
+        return IsEmpty();
+    }
+
     operator bool() const {
         return Chain;
     }
@@ -699,10 +703,7 @@ public:
 
     // Use this method carefully -- it may significantly reduce performance when misused.
     TString ConvertToString() const {
-        // TODO(innokentii): could be microoptimized for single TString case
-        TString res = TString::Uninitialized(GetSize());
-        Begin().ExtractPlainDataAndAdvance(res.Detach(), res.size());
-        return res;
+        return ExtractUnderlyingContainerOrCopy<TString>();
     }
 
     /**
@@ -710,14 +711,14 @@ public:
      */
     template <class TResult>
     TResult ExtractUnderlyingContainerOrCopy() const {
-        if (IsContiguous() && GetSize() != 0) {
-            const auto& chunk = Begin().GetChunk();
-            return chunk.ExtractUnderlyingContainerOrCopy<TResult>();
+        if (Chain.begin() != Chain.end() && ++Chain.begin() == Chain.end()) {
+            return Chain.GetFirstChunk().ExtractUnderlyingContainerOrCopy<TResult>();
         }
 
-        TResult res = TResult::Uninitialized(GetSize());
+        const size_t size = GetSize();
+        TResult res = TResult::Uninitialized(size);
         char* data = NContiguousDataDetails::TContainerTraits<TResult>::UnsafeGetDataMut(res);
-        Begin().ExtractPlainDataAndAdvance(data, res.size());
+        Begin().ExtractPlainDataAndAdvance(data, size);
         return res;
     }
 
diff --git a/ydb/core/base/blobstorage.h b/ydb/core/base/blobstorage.h
index b9ccac76867..b8ff78474bc 100644
--- a/ydb/core/base/blobstorage.h
+++ b/ydb/core/base/blobstorage.h
@@ -1194,7 +1194,7 @@ struct TEvBlobStorage {
             TLogoBlobID Id;
             ui32 Shift;
             ui32 RequestedSize;
-            TString Buffer;
+            TRope Buffer;
             TVector<TPartMapItem> PartMap;
             bool Keep = false;
             bool DoNotKeep = false;
@@ -1245,7 +1245,7 @@ struct TEvBlobStorage {
                     str << " RequestedSize# " << response.RequestedSize;
                 }
                 if (isFull) {
-                    str << " Buffer# " << response.Buffer.Quote();
+                    str << " Buffer# " << response.Buffer.ConvertToString().Quote();
                 }
                 str << "}";
                 if (ErrorReason.size()) {
diff --git a/ydb/core/blob_depot/agent/agent_impl.h b/ydb/core/blob_depot/agent/agent_impl.h
index 1620172c254..7509890e00c 100644
--- a/ydb/core/blob_depot/agent/agent_impl.h
+++ b/ydb/core/blob_depot/agent/agent_impl.h
@@ -149,6 +149,34 @@ namespace NKikimr::NBlobDepot {
         void RegisterRequestInFlight(TRequestInFlight *requestInFlight);
     };
 
+    struct TReadOutcome {
+        struct TOk {
+            TRope Data;
+        };
+        struct TNodata {
+        };
+        struct TError {
+            NKikimrProto::EReplyStatus Status;
+            TString ErrorReason;
+        };
+        std::variant<TOk, TNodata, TError> Value;
+
+        TString ToString() const {
+            return std::visit(TOverloaded{
+                [](const TOk& value) {
+                    return TStringBuilder() << "{Ok Data.size# " << value.Data.size() << "}";
+                },
+                [](const TNodata& /*value*/) {
+                    return TStringBuilder() << "{Nodata}";
+                },
+                [](const TError& value) {
+                    return TStringBuilder() << "{Error Status# " << NKikimrProto::EReplyStatus_Name(value.Status)
+                        << " ErrorReason# " << value.ErrorReason.Quote() << "}";
+                }
+            }, Value);
+        }
+    };
+
     class TBlobDepotAgent
         : public TActorBootstrapped<TBlobDepotAgent>
         , public TRequestSender
@@ -342,7 +370,7 @@ namespace NKikimr::NBlobDepot {
             virtual void Initiate() = 0;
 
             virtual void OnUpdateBlock() {}
-            virtual void OnRead(ui64 /*tag*/, NKikimrProto::EReplyStatus /*status*/, TString /*dataOrErrorReason*/) {}
+            virtual void OnRead(ui64 /*tag*/, TReadOutcome&& /*outcome*/) {}
             virtual void OnIdAllocated(bool /*success*/) {}
             virtual void OnDestroy(bool /*success*/) {}
 
diff --git a/ydb/core/blob_depot/agent/defs.h b/ydb/core/blob_depot/agent/defs.h
index 09f2cba7af1..774204b5915 100644
--- a/ydb/core/blob_depot/agent/defs.h
+++ b/ydb/core/blob_depot/agent/defs.h
@@ -6,6 +6,7 @@
 #include <ydb/core/blob_depot/types.h>
 
 #include <ydb/core/blobstorage/vdisk/common/vdisk_events.h>
+#include <ydb/core/util/fragmented_buffer.h>
 #include <ydb/core/util/stlog.h>
 
 #include <util/generic/hash_multi_map.h>
diff --git a/ydb/core/blob_depot/agent/read.cpp b/ydb/core/blob_depot/agent/read.cpp
index f577a74bfb7..e3c793a1ed8 100644
--- a/ydb/core/blob_depot/agent/read.cpp
+++ b/ydb/core/blob_depot/agent/read.cpp
@@ -8,7 +8,7 @@ namespace NKikimr::NBlobDepot {
     {
         TReadArg ReadArg;
         const ui64 Size;
-        TString Buffer;
+        TFragmentedBuffer Buffer;
         bool Terminated = false;
         bool StopProcessingParts = false;
         ui32 NumPartsPending = 0;
@@ -25,20 +25,22 @@ namespace NKikimr::NBlobDepot {
 
         void EndWithSuccess(TQuery *query) {
             Y_VERIFY(!Terminated);
-            query->OnRead(ReadArg.Tag, NKikimrProto::OK, std::move(Buffer));
+            Y_VERIFY(Buffer.IsMonolith());
+            Y_VERIFY(Buffer.GetMonolith().size() == Size);
+            query->OnRead(ReadArg.Tag, TReadOutcome{TReadOutcome::TOk{Buffer.GetMonolith()}});
             Abort();
         }
 
         void EndWithError(TQuery *query, NKikimrProto::EReplyStatus status, TString errorReason) {
             Y_VERIFY(!Terminated);
             Y_VERIFY(status != NKikimrProto::NODATA && status != NKikimrProto::OK);
-            query->OnRead(ReadArg.Tag, status, errorReason);
+            query->OnRead(ReadArg.Tag, TReadOutcome{TReadOutcome::TError{status, std::move(errorReason)}});
             Abort();
         }
 
         void EndWithNoData(TQuery *query) {
             Y_VERIFY(!Terminated);
-            query->OnRead(ReadArg.Tag, NKikimrProto::NODATA, {});
+            query->OnRead(ReadArg.Tag, TReadOutcome{TReadOutcome::TNodata{}});
             Abort();
         }
 
@@ -188,20 +190,9 @@ namespace NKikimr::NBlobDepot {
                 return readContext.EndWithError(this, blob.Status, TStringBuilder() << "failed to read BlobId# " << blob.Id);
             }
 
-            auto& buffer = readContext.Buffer;
             const ui64 offset = partContext.Offsets[i];
-
             Y_VERIFY(offset < readContext.Size && blob.Buffer.size() <= readContext.Size - offset);
-
-            if (!buffer && !offset) {
-                buffer = std::move(blob.Buffer);
-                buffer.resize(readContext.Size);
-            } else {
-                if (!buffer) {
-                    buffer = TString::Uninitialized(readContext.Size);
-                }
-                memcpy(buffer.Detach() + offset, blob.Buffer.data(), blob.Buffer.size());
-            }
+            readContext.Buffer.Write(offset, std::move(blob.Buffer));
         }
 
         if (!--readContext.NumPartsPending) {
diff --git a/ydb/core/blob_depot/agent/storage_discover.cpp b/ydb/core/blob_depot/agent/storage_discover.cpp
index da5deaf4598..9e5c29c97b8 100644
--- a/ydb/core/blob_depot/agent/storage_discover.cpp
+++ b/ydb/core/blob_depot/agent/storage_discover.cpp
@@ -146,31 +146,28 @@ namespace NKikimr::NBlobDepot {
                 }
             }
 
-            void OnRead(ui64 /*tag*/, NKikimrProto::EReplyStatus status, TString dataOrErrorReason) override {
+            void OnRead(ui64 /*tag*/, TReadOutcome&& outcome) override {
                 STLOG(PRI_DEBUG, BLOB_DEPOT_AGENT, BDA20, "OnRead", (AgentId, Agent.LogId),
-                    (QueryId, GetQueryId()), (Status, status));
+                    (QueryId, GetQueryId()), (Outcome, outcome));
 
-                switch (status) {
-                    case NKikimrProto::OK:
-                        Buffer = std::move(dataOrErrorReason);
+                std::visit(TOverloaded{
+                    [&](TReadOutcome::TOk& ok) {
+                        Buffer = ok.Data.ConvertToString();
                         DoneWithData = true;
                         CheckIfDone();
-                        break;
-
-                    case NKikimrProto::NODATA: {
+                    },
+                    [&](TReadOutcome::TNodata& /*nodata*/) {
                         // we are reading blob from the original group and it may be partially written -- it is totally
                         // okay to have some; we need to advance to the next readable blob
                         auto *range = Resolve.MutableItems(0)->MutableKeyRange();
                         range->SetEndingKey(Id.AsBinaryString());
                         range->ClearIncludeEnding();
                         IssueResolve();
-                        break;
+                    },
+                    [&](TReadOutcome::TError& error) {
+                        EndWithError(error.Status, error.ErrorReason);
                     }
-
-                    default:
-                        EndWithError(status, std::move(dataOrErrorReason));
-                        break;
-                }
+                }, outcome.Value);
             }
 
             void CheckIfDone() {
diff --git a/ydb/core/blob_depot/agent/storage_get.cpp b/ydb/core/blob_depot/agent/storage_get.cpp
index e09c1be28e5..300e9d50dcc 100644
--- a/ydb/core/blob_depot/agent/storage_get.cpp
+++ b/ydb/core/blob_depot/agent/storage_get.cpp
@@ -102,17 +102,28 @@ namespace NKikimr::NBlobDepot {
                 return true;
             }
 
-            void OnRead(ui64 tag, NKikimrProto::EReplyStatus status, TString buffer) override {
+            void OnRead(ui64 tag, TReadOutcome&& outcome) override {
                 STLOG(PRI_DEBUG, BLOB_DEPOT_AGENT, BDA35, "OnRead", (AgentId, Agent.LogId), (QueryId, GetQueryId()),
-                    (Tag, tag), (Status, status), (Buffer.size, status == NKikimrProto::OK ? buffer.size() : 0),
-                    (ErrorReason, status != NKikimrProto::OK ? buffer : ""));
+                    (Tag, tag), (Outcome, outcome));
 
                 auto& resp = Response->Responses[tag];
                 Y_VERIFY(resp.Status == NKikimrProto::UNKNOWN);
-                resp.Status = status;
-                if (status == NKikimrProto::OK) {
-                    resp.Buffer = std::move(buffer);
-                }
+                std::visit(TOverloaded{
+                    [&](TReadOutcome::TOk& ok) {
+                        resp.Status = NKikimrProto::OK;
+                        resp.Buffer = std::move(ok.Data);
+                    },
+                    [&](TReadOutcome::TNodata& /*nodata*/) {
+                        resp.Status = NKikimrProto::NODATA;
+                    },
+                    [&](TReadOutcome::TError& error) {
+                        resp.Status = error.Status;
+                        if (Response->ErrorReason) {
+                            Response->ErrorReason += ", ";
+                        }
+                        Response->ErrorReason += error.ErrorReason;
+                    }
+                }, outcome.Value);
                 --AnswersRemain;
                 CheckAndFinish();
             }
diff --git a/ydb/core/blob_depot/agent/storage_range.cpp b/ydb/core/blob_depot/agent/storage_range.cpp
index c4a736ca96c..b3072aa500c 100644
--- a/ydb/core/blob_depot/agent/storage_range.cpp
+++ b/ydb/core/blob_depot/agent/storage_range.cpp
@@ -114,32 +114,35 @@ namespace NKikimr::NBlobDepot {
                 }
             }
 
-            void OnRead(ui64 tag, NKikimrProto::EReplyStatus status, TString dataOrErrorReason) override {
+            void OnRead(ui64 tag, TReadOutcome&& outcome) override {
                 --ReadsInFlight;
 
                 Y_VERIFY(tag < Reads.size());
                 TRead& read = Reads[tag];
 
-                switch (status) {
-                    case NKikimrProto::OK: {
-                        Y_VERIFY(dataOrErrorReason.size() == read.Id.BlobSize());
-                        const bool inserted = FoundBlobs.try_emplace(read.Id, std::move(dataOrErrorReason)).second;
+                const bool success = std::visit(TOverloaded{
+                    [&](TReadOutcome::TOk& ok) {
+                        Y_VERIFY(ok.Data.size() == read.Id.BlobSize());
+                        const bool inserted = FoundBlobs.try_emplace(read.Id, ok.Data.ConvertToString()).second;
                         Y_VERIFY_S(inserted, "AgentId# " << Agent.LogId << " QueryId# " << GetQueryId()
                             << " duplicate BlobId# " << read.Id << " received");
-                        break;
-                    }
-
-                    case NKikimrProto::NODATA:
+                        return true;
+                    },
+                    [&](TReadOutcome::TNodata& /*nodata*/) {
                         // this blob has just vanished since we found it in index -- may be it was partially written and
                         // now gone; it's okay to have this situation, not a data loss
-                        break;
+                        return true;
+                    },
+                    [&](TReadOutcome::TError& error) {
+                        EndWithError(error.Status, TStringBuilder() << "failed to retrieve BlobId# "
+                            << read.Id << " Error# " << error.ErrorReason);
+                        return false;
+                    }
+                }, outcome.Value);
 
-                    default:
-                        return EndWithError(status, TStringBuilder() << "failed to retrieve BlobId# "
-                            << read.Id << " Error# " << dataOrErrorReason);
+                if (success) {
+                    CheckAndFinish();
                 }
-
-                CheckAndFinish();
             }
 
             void CheckAndFinish() {
diff --git a/ydb/core/blob_depot/assimilator.cpp b/ydb/core/blob_depot/assimilator.cpp
index dd9d4dd5df3..ce05524e84f 100644
--- a/ydb/core/blob_depot/assimilator.cpp
+++ b/ydb/core/blob_depot/assimilator.cpp
@@ -378,7 +378,7 @@ namespace NKikimr::NBlobDepot {
                     const auto blobSeqId = TBlobSeqId::FromSequentalNumber(channel.Index, Self->Executor()->Generation(), value);
                     const TLogoBlobID id = blobSeqId.MakeBlobId(Self->TabletID(), EBlobType::VG_DATA_BLOB, 0, resp.Id.BlobSize());
                     const ui64 putId = NextPutId++;
-                    SendToBSProxy(SelfId(), channel.GroupId, new TEvBlobStorage::TEvPut(id, resp.Buffer, TInstant::Max()), putId);
+                    SendToBSProxy(SelfId(), channel.GroupId, new TEvBlobStorage::TEvPut(id, TRcBuf(resp.Buffer), TInstant::Max()), putId);
                     const bool inserted = channel.AssimilatedBlobsInFlight.insert(value).second; // prevent from barrier advancing
                     Y_VERIFY(inserted);
                     const bool inserted1 = PutIdToKey.try_emplace(putId, TData::TKey(resp.Id), it->first).second;
diff --git a/ydb/core/blob_depot/data_decommit.cpp b/ydb/core/blob_depot/data_decommit.cpp
index c1dda2ef7f1..050845c4c95 100644
--- a/ydb/core/blob_depot/data_decommit.cpp
+++ b/ydb/core/blob_depot/data_decommit.cpp
@@ -245,7 +245,7 @@ namespace NKikimr::NBlobDepot {
         ////////////////////////////////////////////////////////////////////////////////////////////////////////////////
         // PUT QUERIES are used to store retrieved MustRestoreFirst blobs in local storage
 
-        void IssuePut(TKey key, TString&& buffer, bool keep, bool doNotKeep) {
+        void IssuePut(TKey key, TRope&& buffer, bool keep, bool doNotKeep) {
             std::vector<ui8> channels(1);
             if (Self->PickChannels(NKikimrBlobDepot::TChannelKind::Data, channels)) {
                 TChannelInfo& channel = Self->Channels[channels.front()];
@@ -254,7 +254,7 @@ namespace NKikimr::NBlobDepot {
                 const TLogoBlobID id = blobSeqId.MakeBlobId(Self->TabletID(), EBlobType::VG_DATA_BLOB, 0, buffer.size());
                 STLOG(PRI_DEBUG, BLOB_DEPOT, BDT91, "going to TEvPut", (Id, Self->GetLogId()), (Sender, Ev->Sender),
                     (Cookie, Ev->Cookie), (Key, key), (BlobId, id));
-                SendToBSProxy(SelfId(), channel.GroupId, new TEvBlobStorage::TEvPut(id, std::move(buffer), TInstant::Max()),
+                SendToBSProxy(SelfId(), channel.GroupId, new TEvBlobStorage::TEvPut(id, TRcBuf(buffer), TInstant::Max()),
                     (ui64)keep | (ui64)doNotKeep << 1);
                 const bool inserted = channel.AssimilatedBlobsInFlight.insert(value).second; // prevent from barrier advancing
                 Y_VERIFY(inserted);
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy.h b/ydb/core/blobstorage/dsproxy/dsproxy.h
index 6d06f68f795..091bd8df5dc 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy.h
+++ b/ydb/core/blobstorage/dsproxy/dsproxy.h
@@ -596,7 +596,7 @@ void EncryptInplace(TRope& rope, ui32 offset, ui32 size, const TLogoBlobID& id,
 
 void Decrypt(char *destination, const char *source, size_t shift, size_t sizeBytes, const TLogoBlobID &id,
         const TBlobStorageGroupInfo &info);
-void DecryptInplace(TRope& rope, const TLogoBlobID& id, const TBlobStorageGroupInfo& info);
+void DecryptInplace(TRope& rope, ui32 offset, ui32 shift, ui32 size, const TLogoBlobID& id, const TBlobStorageGroupInfo& info);
 
 IActor* CreateBlobStorageGroupRangeRequest(const TIntrusivePtr<TBlobStorageGroupInfo> &info,
     const TIntrusivePtr<TGroupQueues> &state, const TActorId &source,
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_discover.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_discover.cpp
index ca296d76ad3..0f97eae7b36 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_discover.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_discover.cpp
@@ -748,14 +748,14 @@ class TBlobStorageGroupDiscoverRequest : public TBlobStorageGroupRequestActor<TB
                     if (IsGetBlockDone) {
                         std::unique_ptr<TEvBlobStorage::TEvDiscoverResult> result(
                             new TEvBlobStorage::TEvDiscoverResult(
-                                response.Id, MinGeneration, response.Buffer, BlockedGen));
+                                response.Id, MinGeneration, response.Buffer.ConvertToString(), BlockedGen));
                         A_LOG_DEBUG_S("BSD16", "Handle TEvGetResult status# OK Die. TEvDiscoverResult# "
                             << result->Print(false));
                         SendResult(result);
                         return;
                     }
                     PendingResult.reset(new TEvBlobStorage::TEvDiscoverResult(response.Id, MinGeneration,
-                                response.Buffer, BlockedGen));
+                                response.Buffer.ConvertToString(), BlockedGen));
                     A_LOG_DEBUG_S("BSD17", "Handle TEvGetResult status# OK"
                         << " Setting pending result# " << PendingResult->ToString());
                     Y_VERIFY(TotalRecieved < TotalSent);
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3dc.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3dc.cpp
index 31ceba6c386..e85995a2f3e 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3dc.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3dc.cpp
@@ -611,7 +611,7 @@ public:
             case NKikimrProto::OK:
                 // okay response -- blob is read and stored in all replicas
                 Y_VERIFY(resp.Id == ResultBlobId);
-                Buffer = resp.Buffer;
+                Buffer = resp.Buffer.ConvertToString();
                 GetFinished = true;
                 TryToSatisfyRequest();
                 break;
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3of4.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3of4.cpp
index 4e7ff9c2ce7..40a3bf4431c 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3of4.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_discover_m3of4.cpp
@@ -338,8 +338,8 @@ public:
                 break;
 
             case NKikimrProto::OK:
-                SendResponseAndDie(std::make_unique<TEvBlobStorage::TEvDiscoverResult>(resp.Id, MinGeneration, resp.Buffer,
-                    BlockedGeneration));
+                SendResponseAndDie(std::make_unique<TEvBlobStorage::TEvDiscoverResult>(resp.Id, MinGeneration,
+                    resp.Buffer.ConvertToString(), BlockedGeneration));
                 break;
 
             default:
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_encrypt.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_encrypt.cpp
index 62cf2a90fff..06d43748bbb 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_encrypt.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_encrypt.cpp
@@ -70,12 +70,13 @@ namespace NKikimr {
         Encrypt(destination, source, shift, sizeBytes, id, info);
     }
 
-    void DecryptInplace(TRope& rope, const TLogoBlobID& id, const TBlobStorageGroupInfo& info) {
+    void DecryptInplace(TRope& rope, ui32 offset, ui32 shift, ui32 size, const TLogoBlobID& id, const TBlobStorageGroupInfo& info) {
         if (info.GetEncryptionMode() == TBlobStorageGroupInfo::EEM_NONE) {
             return;
         }
         auto span = rope.GetContiguousSpanMut();
-        Decrypt(span.data(), span.data(), 0, span.size(), id, info);
+        Y_VERIFY(offset < span.size() && size <= span.size() - offset);
+        Decrypt(span.data() + offset, span.data() + offset, shift, size, id, info);
     }
 
 } // NKikimr
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_get_impl.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_get_impl.cpp
index ca277ffb8b5..40dcb64808d 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_get_impl.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_get_impl.cpp
@@ -133,10 +133,8 @@ void TGetImpl::PrepareReply(NKikimrProto::EReplyStatus status, TString errorReas
                 ui32 size = query.Size ? Min(query.Size, query.Id.BlobSize() - shift) : query.Id.BlobSize() - shift;
 
                 if (!PhantomCheck) {
-                    TString data = TString::Uninitialized(size);
-                    char *dataBuffer = data.Detach();
-                    blobState.Whole.Data.Read(shift, dataBuffer, size);
-                    Decrypt(dataBuffer, dataBuffer, shift, size, query.Id, *Info);
+                    TRope data = blobState.Whole.Data.Read(shift, size);
+                    DecryptInplace(data, 0, shift, size, query.Id, *Info);
                     outResponse.Buffer = std::move(data);
                     Y_VERIFY(outResponse.Buffer, "%s empty response buffer", RequestPrefix.data());
                     ReplyBytes += outResponse.Buffer.size();
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_patch.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_patch.cpp
index 8950f18d7d3..01621b1fb3e 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_patch.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_patch.cpp
@@ -187,7 +187,7 @@ public:
             return;
         }
 
-        Buffer = result->Responses[0].Buffer;
+        Buffer = result->Responses[0].Buffer.ConvertToString();
         ApplyDiffs();
 
         std::unique_ptr<TEvBlobStorage::TEvPut> put = std::make_unique<TEvBlobStorage::TEvPut>(PatchedId, Buffer, Deadline,
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_put.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_put.cpp
index 1b7d4343712..b5ff53a6b82 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_put.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_put.cpp
@@ -389,7 +389,7 @@ class TBlobStorageGroupPutRequest : public TBlobStorageGroupRequestActor<TBlobSt
             }
             TEvBlobStorage::TEvPut *put;
 
-            DecryptInplace(item.Buffer, item.BlobId, *Info);
+            DecryptInplace(item.Buffer, 0, 0, item.Buffer.size(), item.BlobId, *Info);
 
             ev->Bunch.emplace_back(new IEventHandle(
                 TActorId() /*recipient*/,
diff --git a/ydb/core/blobstorage/dsproxy/dsproxy_range.cpp b/ydb/core/blobstorage/dsproxy/dsproxy_range.cpp
index d1783af11f8..a3925bf52c1 100644
--- a/ydb/core/blobstorage/dsproxy/dsproxy_range.cpp
+++ b/ydb/core/blobstorage/dsproxy/dsproxy_range.cpp
@@ -283,7 +283,7 @@ class TBlobStorageGroupRangeRequest : public TBlobStorageGroupRequestActor<TBlob
             Y_VERIFY(response.Id == BlobsToGet[i].BlobId);
 
             if (getResult.Responses[i].Status == NKikimrProto::OK) {
-                result->Responses.emplace_back(response.Id, std::move(response.Buffer), response.Keep, response.DoNotKeep);
+                result->Responses.emplace_back(response.Id, response.Buffer.ConvertToString(), response.Keep, response.DoNotKeep);
             } else if (getResult.Responses[i].Status != NKikimrProto::NODATA || BlobsToGet[i].RequiredToBePresent) {
                 // it's okay to get NODATA if blob wasn't confirmed -- this blob is simply thrown out of resulting
                 // set; otherwise we return error about lost data
diff --git a/ydb/core/blobstorage/dsproxy/mock/model.h b/ydb/core/blobstorage/dsproxy/mock/model.h
index ead4f90bb6b..608b95bfafd 100644
--- a/ydb/core/blobstorage/dsproxy/mock/model.h
+++ b/ydb/core/blobstorage/dsproxy/mock/model.h
@@ -129,7 +129,8 @@ namespace NFake {
                     const ui32 size = Min<ui32>(maxSize, !query.Size ? Max<ui32>() : query.Size);
 
                     // calculate substring; use 0 instead of query.Shift because it may exceed the buffer
-                    response.Buffer = data.Buffer.ConvertToString().substr(size ? query.Shift : 0, size);
+                    const ui32 offset = size ? query.Shift : 0;
+                    response.Buffer = TRope(data.Buffer.Position(offset), data.Buffer.Position(offset + size));
                 } else {
                     // ensure this blob is not under GC
                     Y_VERIFY(!IsCollectedByBarrier(id), "Id# %s", id.ToString().data());
diff --git a/ydb/core/blobstorage/dsproxy/ut/dsproxy_get_ut.cpp b/ydb/core/blobstorage/dsproxy/ut/dsproxy_get_ut.cpp
index 59f0c116c3c..638f4bc5975 100644
--- a/ydb/core/blobstorage/dsproxy/ut/dsproxy_get_ut.cpp
+++ b/ydb/core/blobstorage/dsproxy/ut/dsproxy_get_ut.cpp
@@ -120,7 +120,7 @@ void TestIntervalsAndCrcAllOk(TErasureType::EErasureSpecies erasureSpecies, bool
                 UNIT_ASSERT_VALUES_EQUAL(a.Status, NKikimrProto::OK);
                 UNIT_ASSERT_VALUES_EQUAL(q.Shift, a.Shift);
                 UNIT_ASSERT_VALUES_EQUAL(q.Size, a.RequestedSize);
-                blobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer);
+                blobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer.ConvertToString());
             }
         }
     }
@@ -451,7 +451,7 @@ private:
             UNIT_ASSERT_VALUES_EQUAL(a.Status, NKikimrProto::OK);
             UNIT_ASSERT_VALUES_EQUAL(q.Shift, a.Shift);
             UNIT_ASSERT_VALUES_EQUAL(q.Size, a.RequestedSize);
-            BlobSet->Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer);
+            BlobSet->Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer.ConvertToString());
         }
     }
 };
@@ -765,7 +765,7 @@ Y_UNIT_TEST(TestBlock42VGetCountWithErasure) {
             if (a.Status == NKikimrProto::OK) {
                 UNIT_ASSERT_VALUES_EQUAL(q.Shift, a.Shift);
                 UNIT_ASSERT_VALUES_EQUAL(q.Size, a.RequestedSize);
-                blobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer);
+                blobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer.ConvertToString());
             } else {
                 TStringStream str;
                 str << " isRestore# " << isRestore
@@ -909,7 +909,7 @@ Y_UNIT_TEST(TestBlock42WipedOneDiskAndErrorDurringGet) {
             if (a.Status == NKikimrProto::OK) {
                 UNIT_ASSERT_VALUES_EQUAL(q.Shift, a.Shift);
                 UNIT_ASSERT_VALUES_EQUAL(q.Size, a.RequestedSize);
-                blobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer);
+                blobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer.ConvertToString());
             } else {
                 TStringStream str;
                 str << " isRestore# " << isRestore
@@ -1007,7 +1007,7 @@ void TestIntervalsWipedError(TErasureType::EErasureSpecies erasureSpecies, bool
                                                 if (a.Status == NKikimrProto::OK) {
                                                     UNIT_ASSERT_VALUES_EQUAL(q.Shift, a.Shift);
                                                     UNIT_ASSERT_VALUES_EQUAL(q.Size, a.RequestedSize);
-                                                    simulator.BlobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer);
+                                                    simulator.BlobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer.ConvertToString());
                                                 } else {
                                                     TStringStream str;
                                                     str << " isRestore# " << isRestore
@@ -1183,7 +1183,7 @@ void TestWipedErrorWithTwoBlobs(TErasureType::EErasureSpecies erasureSpecies, bo
                                 if (a.Status == NKikimrProto::OK) {
                                     UNIT_ASSERT_VALUES_EQUAL(q.Shift, a.Shift);
                                     UNIT_ASSERT_VALUES_EQUAL(q.Size, a.RequestedSize);
-                                    blobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer);
+                                    blobSet.Check(queryIdx % blobCount, q.Id, q.Shift, q.Size, a.Buffer.ConvertToString());
                                 } else {
                                     TStringStream str;
                                     str << " isRestore# " << isRestore
@@ -1280,7 +1280,7 @@ void SpecificTest(ui32 badA, ui32 badB, ui32 blobSize, TMap<i64, i64> sizeForOff
             if (a.Status == NKikimrProto::OK) {
                 UNIT_ASSERT_VALUES_EQUAL(qb.Shift, a.Shift);
                 UNIT_ASSERT_VALUES_EQUAL(qb.Size, a.RequestedSize);
-                simulator.BlobSet.Check(0, qb.Id, qb.Shift, qb.Size, a.Buffer);
+                simulator.BlobSet.Check(0, qb.Id, qb.Shift, qb.Size, a.Buffer.ConvertToString());
             } else {
                 TStringStream str;
                 str << " isRestore# false setIdx# 0 status# " << a.Status;
@@ -1492,7 +1492,7 @@ public:
                 UNIT_ASSERT_VALUES_EQUAL_C(a.Status, NKikimrProto::OK, currentTestState.Str());
                 UNIT_ASSERT_VALUES_EQUAL_C(q.Shift, a.Shift, currentTestState.Str());
                 UNIT_ASSERT_VALUES_EQUAL_C(q.Size, a.RequestedSize, currentTestState.Str());
-                BlobSet.Check(queryIdx, q.Id, q.Shift, q.Size, a.Buffer);
+                BlobSet.Check(queryIdx, q.Id, q.Shift, q.Size, a.Buffer.ConvertToString());
             }
         }
         RequestsOrder.resize(InitialRequestsSize);
@@ -1711,7 +1711,7 @@ public:
             UNIT_ASSERT_VALUES_EQUAL(a.Status, NKikimrProto::OK);
             UNIT_ASSERT_VALUES_EQUAL(q.Shift, a.Shift);
             UNIT_ASSERT_VALUES_EQUAL(q.Size, a.RequestedSize);
-            BlobSet.Check(queryIdx, q.Id, q.Shift, q.Size, a.Buffer);
+            BlobSet.Check(queryIdx, q.Id, q.Shift, q.Size, a.Buffer.ConvertToString());
         }
     }
 };
diff --git a/ydb/core/blobstorage/dsproxy/ut/dsproxy_patch_ut.cpp b/ydb/core/blobstorage/dsproxy/ut/dsproxy_patch_ut.cpp
index 151a316c2ce..6639d79f134 100644
--- a/ydb/core/blobstorage/dsproxy/ut/dsproxy_patch_ut.cpp
+++ b/ydb/core/blobstorage/dsproxy/ut/dsproxy_patch_ut.cpp
@@ -303,7 +303,7 @@ void ConductGet(TTestBasicRuntime &runtime, const TTestArgs &args, ENaivePatchCa
             getResult->Responses[0].Id = args.OriginalId;
             getResult->Responses[0].Status = NKikimrProto::ERROR;
         } else {
-            getResult->Responses[0].Buffer = args.Buffer;
+            getResult->Responses[0].Buffer = TRope(args.Buffer);
             getResult->Responses[0].Id = args.OriginalId;
             getResult->Responses[0].Status = NKikimrProto::OK;
         }
diff --git a/ydb/core/blobstorage/dsproxy/ut/dsproxy_sequence_ut.cpp b/ydb/core/blobstorage/dsproxy/ut/dsproxy_sequence_ut.cpp
index 42aeb6db2ba..f6c35e627c0 100644
--- a/ydb/core/blobstorage/dsproxy/ut/dsproxy_sequence_ut.cpp
+++ b/ydb/core/blobstorage/dsproxy/ut/dsproxy_sequence_ut.cpp
@@ -1227,7 +1227,7 @@ Y_UNIT_TEST(TestGivenBlock42PutWhenPartialGetThenSingleDiskRequestOk) {
                 UNIT_ASSERT_C(getResult->Responses[0].Status == NKikimrProto::OK, "Status# " <<
                     NKikimrProto::EReplyStatus_Name(getResult->Responses[0].Status));
                 TString expectedData = data.substr(shift, size);
-                TString actualData = getResult->Responses[0].Buffer;
+                TString actualData = getResult->Responses[0].Buffer.ConvertToString();
                 UNIT_ASSERT_STRINGS_EQUAL_C(expectedData, actualData, "ExpectedSize# " << expectedData.size()
                     << " resultSize$ " << actualData.size() << " part# " << part << " disk# " << disk
                     << " expectedFirst# " << (ui32) (ui8) expectedData[0] << " actualFirst# " <<
diff --git a/ydb/core/blobstorage/dsproxy/ut_fat/dsproxy_ut.cpp b/ydb/core/blobstorage/dsproxy/ut_fat/dsproxy_ut.cpp
index a7ae711ba71..04fea4b01c4 100644
--- a/ydb/core/blobstorage/dsproxy/ut_fat/dsproxy_ut.cpp
+++ b/ydb/core/blobstorage/dsproxy/ut_fat/dsproxy_ut.cpp
@@ -454,8 +454,8 @@ protected:
                 VERBOSE_COUT("  response[" << i <<"]: " << StatusToString(response.Status));
                 if (response.Status == NKikimrProto::OK) {
                     //TODO: Process response.Id (should be same logoblobid as in request)
-                    LastResponse.Data[i] = response.Buffer;
-                    VERBOSE_COUT(" shift: " << response.Shift << " data: " << response.Buffer.c_str());
+                    LastResponse.Data[i] = response.Buffer.ConvertToString();
+                    VERBOSE_COUT(" shift: " << response.Shift << " data: " << response.Buffer.ConvertToString());
                 }
             }
         }
diff --git a/ydb/core/blobstorage/dsproxy/ut_ftol/dsproxy_fault_tolerance_ut_base.h b/ydb/core/blobstorage/dsproxy/ut_ftol/dsproxy_fault_tolerance_ut_base.h
index ef7ae14e611..72e227eea78 100644
--- a/ydb/core/blobstorage/dsproxy/ut_ftol/dsproxy_fault_tolerance_ut_base.h
+++ b/ydb/core/blobstorage/dsproxy/ut_ftol/dsproxy_fault_tolerance_ut_base.h
@@ -166,7 +166,7 @@ public:
         UNIT_ASSERT_VALUES_EQUAL(msg->ResponseSz, 1);
         const TEvBlobStorage::TEvGetResult::TResponse& item = msg->Responses[0];
         if (data) {
-            *data = item.Buffer;
+            *data = item.Buffer.ConvertToString();
         }
         return item.Status;
     }
diff --git a/ydb/core/blobstorage/groupinfo/ut/ya.make b/ydb/core/blobstorage/groupinfo/ut/ya.make
index 2be8b98663d..b3787a39aed 100644
--- a/ydb/core/blobstorage/groupinfo/ut/ya.make
+++ b/ydb/core/blobstorage/groupinfo/ut/ya.make
@@ -25,7 +25,7 @@ SRCS(
     blobstorage_groupinfo_ut.cpp
 )
 
-IF (BUILD_TYPE == "RELEASE")
+IF (BUILD_TYPE != "DEBUG")
     SRCS(
         blobstorage_groupinfo_blobmap_ut.cpp
         blobstorage_groupinfo_partlayout_ut.cpp
diff --git a/ydb/core/blobstorage/other/mon_get_blob_page.cpp b/ydb/core/blobstorage/other/mon_get_blob_page.cpp
index 95308879a33..8814ebd17f1 100644
--- a/ydb/core/blobstorage/other/mon_get_blob_page.cpp
+++ b/ydb/core/blobstorage/other/mon_get_blob_page.cpp
@@ -59,7 +59,7 @@ namespace {
                 } else {
                     result.LogoBlobId = msg->Responses[0].Id;
                     result.Status = msg->Responses[0].Status;
-                    result.Buffer = msg->Responses[0].Buffer;
+                    result.Buffer = msg->Responses[0].Buffer.ConvertToString();
                     result.PartMap = std::move(msg->Responses[0].PartMap);
                 }
                 result.DebugInfo = std::move(msg->DebugInfo);
diff --git a/ydb/core/blobstorage/pdisk/ut/ya.make b/ydb/core/blobstorage/pdisk/ut/ya.make
index f6d01054c4d..ff8f3e0ce4b 100644
--- a/ydb/core/blobstorage/pdisk/ut/ya.make
+++ b/ydb/core/blobstorage/pdisk/ut/ya.make
@@ -39,7 +39,7 @@ SRCS(
     mock/pdisk_mock.cpp
 )
 
-IF (BUILD_TYPE == "RELEASE")
+IF (BUILD_TYPE != "DEBUG")
     SRCS(
         blobstorage_pdisk_ut_yard.cpp
     )
diff --git a/ydb/core/blobstorage/ut_blobstorage/blob_depot_event_managers.cpp b/ydb/core/blobstorage/ut_blobstorage/blob_depot_event_managers.cpp
index ec262c1fb80..8751595d1f9 100644
--- a/ydb/core/blobstorage/ut_blobstorage/blob_depot_event_managers.cpp
+++ b/ydb/core/blobstorage/ut_blobstorage/blob_depot_event_managers.cpp
@@ -169,7 +169,7 @@ void VerifyTEvGetResult(TAutoPtr<TEventHandle<TEvBlobStorage::TEvGetResult>> res
                 UNIT_ASSERT_VALUES_UNEQUAL(responses[0].Status, NKikimrProto::NODATA);
             }
             if (responses[0].Status == NKikimrProto::OK && !isIndexOnly) {
-                UNIT_ASSERT_VALUES_EQUAL(responses[0].Buffer, blob.Data);
+                UNIT_ASSERT_VALUES_EQUAL(responses[0].Buffer.ConvertToString(), blob.Data);
             }
         } else if (blob.Status == TBlobInfo::EStatus::UNKNOWN) {
             if (mustRestoreFirst && responses[0].Status == NKikimrProto::OK) {
@@ -255,7 +255,7 @@ void VerifyTEvGetResult(TAutoPtr<TEventHandle<TEvBlobStorage::TEvGetResult>> res
             } else if (blobs[i].Status == TBlobInfo::EStatus::WRITTEN) {
                 UNIT_ASSERT_VALUES_UNEQUAL(responses[i].Status, NKikimrProto::NODATA);
                 if (responses[i].Status == NKikimrProto::OK && !isIndexOnly) {
-                    UNIT_ASSERT_VALUES_EQUAL(responses[i].Buffer, blobs[i].Data);
+                    UNIT_ASSERT_VALUES_EQUAL(responses[i].Buffer.ConvertToString(), blobs[i].Data);
                 }
             } else if (blobs[i].Status == TBlobInfo::EStatus::UNKNOWN) {
                 if (mustRestoreFirst && responses[i].Status == NKikimrProto::OK) {
diff --git a/ydb/core/blobstorage/ut_blobstorage/counting_events.cpp b/ydb/core/blobstorage/ut_blobstorage/counting_events.cpp
index f3397ec388b..3b26ca9e223 100644
--- a/ydb/core/blobstorage/ut_blobstorage/counting_events.cpp
+++ b/ydb/core/blobstorage/ut_blobstorage/counting_events.cpp
@@ -39,7 +39,7 @@ Y_UNIT_TEST_SUITE(CountingEvents) {
         UNIT_ASSERT(getResult);
         UNIT_ASSERT_VALUES_EQUAL(getResult->ResponseSz, 1);
         UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Status, status);
-        UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Buffer, data);
+        UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Buffer.ConvertToString(), data);
     };
 
     void SendCollect(const TTestInfo &test, const TLogoBlobID &blobId,
diff --git a/ydb/core/blobstorage/ut_blobstorage/discover.cpp b/ydb/core/blobstorage/ut_blobstorage/discover.cpp
index 976ad9f4904..ab65e20e055 100644
--- a/ydb/core/blobstorage/ut_blobstorage/discover.cpp
+++ b/ydb/core/blobstorage/ut_blobstorage/discover.cpp
@@ -23,7 +23,7 @@ Y_UNIT_TEST_SUITE(Discover) {
         UNIT_ASSERT_VALUES_EQUAL(getResult->ResponseSz, 1);
         UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Status, status);
         if (status == NKikimrProto::EReplyStatus::OK) {
-            UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Buffer, data);
+            UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Buffer.ConvertToString(), data);
         }
     }
 
diff --git a/ydb/core/blobstorage/ut_blobstorage/get.cpp b/ydb/core/blobstorage/ut_blobstorage/get.cpp
index 3d3b101dc0b..c0ebf5da0a7 100644
--- a/ydb/core/blobstorage/ut_blobstorage/get.cpp
+++ b/ydb/core/blobstorage/ut_blobstorage/get.cpp
@@ -29,7 +29,7 @@ Y_UNIT_TEST_SUITE(Get) {
         UNIT_ASSERT_VALUES_EQUAL(getResult->ResponseSz, 1);
         UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Status, status);
         if (checkResultData && status == NKikimrProto::EReplyStatus::OK) {
-            UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Buffer, data);
+            UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Buffer.ConvertToString(), data);
         }
     }
 
diff --git a/ydb/core/blobstorage/ut_blobstorage/lib/activity.h b/ydb/core/blobstorage/ut_blobstorage/lib/activity.h
index 8c6f3bfd486..9e4c0cb7017 100644
--- a/ydb/core/blobstorage/ut_blobstorage/lib/activity.h
+++ b/ydb/core/blobstorage/ut_blobstorage/lib/activity.h
@@ -122,7 +122,7 @@ public:
         UNIT_ASSERT_VALUES_EQUAL(response.Status, NKikimrProto::OK);
         UNIT_ASSERT_EQUAL(response.Status, NKikimrProto::OK);
         if (Committed.count(response.Id)) {
-            UNIT_ASSERT_VALUES_EQUAL(Committed.at(response.Id), response.Buffer);
+            UNIT_ASSERT_VALUES_EQUAL(Committed.at(response.Id), response.Buffer.ConvertToString());
             Committed.erase(response.Id);
         }
         if (!--ReadsInFlight) {
diff --git a/ydb/core/blobstorage/ut_blobstorage/patch.cpp b/ydb/core/blobstorage/ut_blobstorage/patch.cpp
index b68c05b80ef..b35e3930dfb 100644
--- a/ydb/core/blobstorage/ut_blobstorage/patch.cpp
+++ b/ydb/core/blobstorage/ut_blobstorage/patch.cpp
@@ -34,7 +34,7 @@ Y_UNIT_TEST_SUITE(BlobPatching) {
         UNIT_ASSERT(getResult);
         UNIT_ASSERT_VALUES_EQUAL(getResult->ResponseSz, 1);
         UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Status, status);
-        UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Buffer, data);
+        UNIT_ASSERT_VALUES_EQUAL(getResult->Responses[0].Buffer.ConvertToString(), data);
     };
 
     void SendPatch(const TTestInfo &test, const TLogoBlobID &originalBlobId, const TLogoBlobID &patchedBlobId, ui32 mask,
diff --git a/ydb/core/blobstorage/ut_blobstorage/scrub_fast.cpp b/ydb/core/blobstorage/ut_blobstorage/scrub_fast.cpp
index b0e49b75fdc..f88f6245bfe 100644
--- a/ydb/core/blobstorage/ut_blobstorage/scrub_fast.cpp
+++ b/ydb/core/blobstorage/ut_blobstorage/scrub_fast.cpp
@@ -39,7 +39,7 @@ void Test() {
         auto& r = res->Get()->Responses[0];
         UNIT_ASSERT_VALUES_EQUAL(r.Status, status);
         if (status == NKikimrProto::OK) {
-            UNIT_ASSERT_VALUES_EQUAL(r.Buffer, data);
+            UNIT_ASSERT_VALUES_EQUAL(r.Buffer.ConvertToString(), data);
         }
     };
 
diff --git a/ydb/core/blobstorage/ut_blobstorage/ya.make b/ydb/core/blobstorage/ut_blobstorage/ya.make
index d0d30e53743..6fd28749c28 100644
--- a/ydb/core/blobstorage/ut_blobstorage/ya.make
+++ b/ydb/core/blobstorage/ut_blobstorage/ya.make
@@ -31,7 +31,7 @@ SRCS(
     sync.cpp
 )
 
-IF (BUILD_TYPE == "RELEASE")
+IF (BUILD_TYPE != "DEBUG")
     SRCS(
         big_cluster.cpp
         get.cpp
diff --git a/ydb/core/blobstorage/ut_group/main.cpp b/ydb/core/blobstorage/ut_group/main.cpp
index 07a0801130a..3c6b4ba17e5 100644
--- a/ydb/core/blobstorage/ut_group/main.cpp
+++ b/ydb/core/blobstorage/ut_group/main.cpp
@@ -532,7 +532,7 @@ public:
                     Y_VERIFY(response.Status == NKikimrProto::OK);
                     const auto it = Committed.find(response.Id);
                     Y_VERIFY(it != Committed.end());
-                    Y_VERIFY(it->second == response.Buffer);
+                    Y_VERIFY(it->second == response.Buffer.ConvertToString());
                     Committed.erase(it);
                 }
                 --readsInFlight;
diff --git a/ydb/core/blobstorage/ut_pdiskfit/ut/ya.make b/ydb/core/blobstorage/ut_pdiskfit/ut/ya.make
index 6f64babbe77..b4e9ff9707b 100644
--- a/ydb/core/blobstorage/ut_pdiskfit/ut/ya.make
+++ b/ydb/core/blobstorage/ut_pdiskfit/ut/ya.make
@@ -7,7 +7,7 @@ IF (OS_LINUX AND NOT WITH_VALGRIND)
 
     TAG(ya:fat)
 
-    IF (BUILD_TYPE == "RELEASE")
+    IF (BUILD_TYPE != "DEBUG")
         SRCS(
             main.cpp
         )
diff --git a/ydb/core/blobstorage/vdisk/skeleton/skeleton_vmovedpatch_actor.cpp b/ydb/core/blobstorage/vdisk/skeleton/skeleton_vmovedpatch_actor.cpp
index 6a03ebf0c5f..d3d1506342a 100644
--- a/ydb/core/blobstorage/vdisk/skeleton/skeleton_vmovedpatch_actor.cpp
+++ b/ydb/core/blobstorage/vdisk/skeleton/skeleton_vmovedpatch_actor.cpp
@@ -136,7 +136,7 @@ namespace NKikimr {
                     return;
                 }
 
-                Buffer = result->Responses[0].Buffer;
+                Buffer = result->Responses[0].Buffer.ConvertToString();
                 ApplyDiffs();
                 TInstant deadline = TActivationContext::Now() + TDuration::MilliSeconds(SubRequestDurationMs);
 
diff --git a/ydb/core/client/server/msgbus_server_get.cpp b/ydb/core/client/server/msgbus_server_get.cpp
index 326de522b12..b912bea015f 100644
--- a/ydb/core/client/server/msgbus_server_get.cpp
+++ b/ydb/core/client/server/msgbus_server_get.cpp
@@ -52,7 +52,7 @@ public:
         if (msg->Status == NKikimrProto::OK && msg->ResponseSz == 1) {
             const TEvBlobStorage::TEvGetResult::TResponse& resp = msg->Responses[0];
             Response.SetStatus(resp.Status);
-            Response.SetBuffer(resp.Buffer);
+            Response.SetBuffer(resp.Buffer.ConvertToString());
         }
         IssueResponse(ctx);
     }
diff --git a/ydb/core/keyvalue/keyvalue_storage_read_request.cpp b/ydb/core/keyvalue/keyvalue_storage_read_request.cpp
index 4d91fef7ee4..9b248b62e67 100644
--- a/ydb/core/keyvalue/keyvalue_storage_read_request.cpp
+++ b/ydb/core/keyvalue/keyvalue_storage_read_request.cpp
@@ -294,7 +294,8 @@ public:
                         "readItem.ValueOffset# " << readItem.ValueOffset
                         << " readItem.BlobSize# " << readItem.BlobSize
                         << " read.ValueSize# " << read.ValueSize);
-                memcpy(const_cast<char *>(read.Value.data()) + readItem.ValueOffset, response.Buffer.data(), response.Buffer.size());
+                Y_VERIFY(read.Value.IsDetached());
+                response.Buffer.begin().ExtractPlainDataAndAdvance(read.Value.Detach() + readItem.ValueOffset, response.Buffer.size());
                 IntermediateResult->Stat.GroupReadBytes[std::make_pair(response.Id.Channel(), batch.GroupId)] += response.Buffer.size();
                 // FIXME: count distinct blobs?" keyvalue_storage_request.cpp:279
                 IntermediateResult->Stat.GroupReadIops[std::make_pair(response.Id.Channel(), batch.GroupId)] += 1;
diff --git a/ydb/core/keyvalue/keyvalue_storage_read_request_ut.cpp b/ydb/core/keyvalue/keyvalue_storage_read_request_ut.cpp
index 2ce080f54b9..224c0b86cac 100644
--- a/ydb/core/keyvalue/keyvalue_storage_read_request_ut.cpp
+++ b/ydb/core/keyvalue/keyvalue_storage_read_request_ut.cpp
@@ -46,11 +46,16 @@ struct TBlobStorageMockState {
             response.Id = query.Id;
             response.Shift = query.Shift;
             response.RequestedSize = query.Size;
-            std::tie(response.Status, response.Buffer) = getBlob(query.Id);
+
+            TString r;
+            std::tie(response.Status, r) = getBlob(query.Id);
+
             if (response.Status == NKikimrProto::OK) {
-                TString buffer = TString::Uninitialized(query.Size);
-                memcpy(const_cast<char *>(buffer.data()), response.Buffer.data() + query.Shift, response.Buffer.size());
-                response.Buffer = buffer;
+                const size_t shift = Min<size_t>(query.Shift, r.size());
+                const size_t size = Min<size_t>(query.Size ? query.Size : Max<size_t>(), r.size() - shift);
+                TString buffer = TString::Uninitialized(size);
+                memcpy(buffer.Detach(), r.data() + shift, size);
+                response.Buffer = TRope(std::move(buffer));
             }
         }
         return getResult;
diff --git a/ydb/core/keyvalue/keyvalue_storage_request.cpp b/ydb/core/keyvalue/keyvalue_storage_request.cpp
index 1522e0b22f0..4f24557e6b8 100644
--- a/ydb/core/keyvalue/keyvalue_storage_request.cpp
+++ b/ydb/core/keyvalue/keyvalue_storage_request.cpp
@@ -280,7 +280,7 @@ public:
         auto groupId = ev->Get()->GroupId;
         decltype(request.ReadQueue)::iterator it = request.ReadQueue.begin();
         for (ui32 i = 0, num = ev->Get()->ResponseSz; i < num; ++i, ++it) {
-            const auto& response = ev->Get()->Responses[i];
+            auto& response = ev->Get()->Responses[i];
             auto& read = *it->Read;
             auto& readItem = *it->ReadItem;
 
@@ -290,7 +290,8 @@ public:
                 }
                 Y_VERIFY(response.Buffer.size() == readItem.BlobSize);
                 Y_VERIFY(readItem.ValueOffset + readItem.BlobSize <= read.ValueSize);
-                memcpy(const_cast<char *>(read.Value.data()) + readItem.ValueOffset, response.Buffer.data(), response.Buffer.size());
+                Y_VERIFY(read.Value.IsDetached());
+                response.Buffer.begin().ExtractPlainDataAndAdvance(read.Value.Detach() + readItem.ValueOffset, response.Buffer.size());
                 IntermediateResults->Stat.GroupReadBytes[std::make_pair(response.Id.Channel(), groupId)] += response.Buffer.size();
                 IntermediateResults->Stat.GroupReadIops[std::make_pair(response.Id.Channel(), groupId)] += 1; // FIXME: count distinct blobs?
             } else {
diff --git a/ydb/core/mind/ut_fat/blobstorage_node_warden_ut_fat.cpp b/ydb/core/mind/ut_fat/blobstorage_node_warden_ut_fat.cpp
index d78e767c970..98ba8a7b5f5 100644
--- a/ydb/core/mind/ut_fat/blobstorage_node_warden_ut_fat.cpp
+++ b/ydb/core/mind/ut_fat/blobstorage_node_warden_ut_fat.cpp
@@ -349,7 +349,7 @@ Y_UNIT_TEST_SUITE(TBlobStorageWardenTest) {
         UNIT_ASSERT(getResult->ResponseSz == 1);
         UNIT_ASSERT(getResult->Responses.Get());
         UNIT_ASSERT_EQUAL((getResult->Responses)[0].Buffer.size(), data.size());
-        UNIT_ASSERT_EQUAL((getResult->Responses)[0].Buffer, data);
+        UNIT_ASSERT_EQUAL((getResult->Responses)[0].Buffer.ConvertToString(), data);
     }
 
     void VGet(TTestActorRuntime &runtime, TActorId &sender, ui32 groupId, ui32 nodeId, TLogoBlobID logoBlobId,
diff --git a/ydb/core/tablet_flat/flat_bio_actor.cpp b/ydb/core/tablet_flat/flat_bio_actor.cpp
index 9bbb4e1a211..d91ae40319b 100644
--- a/ydb/core/tablet_flat/flat_bio_actor.cpp
+++ b/ydb/core/tablet_flat/flat_bio_actor.cpp
@@ -161,10 +161,7 @@ void TBlockIO::Handle(ui32 base, TArrayRef<TLoaded> items) noexcept
 
         auto& state = BlockStates.at(brick.Slot);
         Y_VERIFY(state.Data.size() - state.Offset >= piece.Buffer.size());
-        ::memcpy(
-            state.Data.mutable_data() + state.Offset,
-            piece.Buffer.data(),
-            piece.Buffer.size());
+        piece.Buffer.begin().ExtractPlainDataAndAdvance(state.Data.mutable_data() + state.Offset, piece.Buffer.size());
         state.Offset += piece.Buffer.size();
     }
 
diff --git a/ydb/core/tablet_flat/flat_load_blob_queue.cpp b/ydb/core/tablet_flat/flat_load_blob_queue.cpp
index 3c97b4a5359..ef6369f010d 100644
--- a/ydb/core/tablet_flat/flat_load_blob_queue.cpp
+++ b/ydb/core/tablet_flat/flat_load_blob_queue.cpp
@@ -171,11 +171,13 @@ bool TLoadBlobQueue::ProcessResult(TEvBlobStorage::TEvGetResult* msg) {
 
         ActiveBytesInFly -= x->Id.BlobSize();
 
+        TString buffer = x->Buffer.ConvertToString();
+
         if (std::next(p.first) == p.second) {
             // Common case: unique load of the blob
             auto item = p.first->second;
             Active.erase(p.first);
-            item.Load->OnBlobLoaded(x->Id, std::move(x->Buffer), item.Cookie);
+            item.Load->OnBlobLoaded(x->Id, std::move(buffer), item.Cookie);
         } else {
             // May rarely happen: concurrent load of the same blob
             TVector<TActiveItem> items;
@@ -188,10 +190,10 @@ bool TLoadBlobQueue::ProcessResult(TEvBlobStorage::TEvGetResult* msg) {
             size_t last = items.size() - 1;
             for (size_t i = 0; i < last; ++i) {
                 // We have to make a copy of the buffer
-                items[i].Load->OnBlobLoaded(x->Id, x->Buffer, items[i].Cookie);
+                items[i].Load->OnBlobLoaded(x->Id, buffer, items[i].Cookie);
             }
             // Last load may consume our buffer
-            items[last].Load->OnBlobLoaded(x->Id, std::move(x->Buffer), items[last].Cookie);
+            items[last].Load->OnBlobLoaded(x->Id, std::move(buffer), items[last].Cookie);
         }
     }
 
diff --git a/ydb/core/tx/columnshard/blob_cache.cpp b/ydb/core/tx/columnshard/blob_cache.cpp
index 4d1c8ca3325..a0edefcbf94 100644
--- a/ydb/core/tx/columnshard/blob_cache.cpp
+++ b/ydb/core/tx/columnshard/blob_cache.cpp
@@ -520,7 +520,7 @@ private:
             if (res.Status == NKikimrProto::EReplyStatus::NODATA) {
                 fallbackRanges[blobRanges[i].BlobId].emplace_back(std::move(blobRanges[i]));
             } else {
-                ProcessSingleRangeResult(blobRanges[i], readCookie, res.Status, res.Buffer, ctx);
+                ProcessSingleRangeResult(blobRanges[i], readCookie, res.Status, res.Buffer.ConvertToString(), ctx);
             }
         }