diff --git a/ydb/core/kqp/ut/olap/blobs_sharing_ut.cpp b/ydb/core/kqp/ut/olap/blobs_sharing_ut.cpp
index cfbdd117d3e9..70d3a20fd7e2 100644
--- a/ydb/core/kqp/ut/olap/blobs_sharing_ut.cpp
+++ b/ydb/core/kqp/ut/olap/blobs_sharing_ut.cpp
@@ -100,7 +100,7 @@ Y_UNIT_TEST_SUITE(KqpOlapBlobsSharing) {
             Controller->SetCompactionControl(NYDBTest::EOptimizerCompactionWeightControl::Disable);
             Controller->SetExpectedShardsCount(ShardsCount);
             Controller->SetOverridePeriodicWakeupActivationPeriod(TDuration::Seconds(1));
-            Controller->SetOverrideReadTimeoutClean(TDuration::Seconds(1));
+            Controller->SetOverrideMaxReadStaleness(TDuration::Seconds(1));
 
             Tests::NCommon::TLoggerInit(Kikimr).SetComponents({ NKikimrServices::TX_COLUMNSHARD }, "CS").Initialize();
 
@@ -117,7 +117,7 @@ Y_UNIT_TEST_SUITE(KqpOlapBlobsSharing) {
         }
 
         void WaitNormalization() {
-            Controller->SetOverrideReadTimeoutClean(TDuration::Seconds(1));
+            Controller->SetOverrideMaxReadStaleness(TDuration::Seconds(1));
             Controller->SetCompactionControl(NYDBTest::EOptimizerCompactionWeightControl::Force);
             const auto start = TInstant::Now();
             while (!Controller->IsTrivialLinks() && TInstant::Now() - start < TDuration::Seconds(30)) {
@@ -126,11 +126,11 @@ Y_UNIT_TEST_SUITE(KqpOlapBlobsSharing) {
             }
             AFL_VERIFY(Controller->IsTrivialLinks());
             Controller->CheckInvariants();
-            Controller->SetOverrideReadTimeoutClean(TDuration::Minutes(5));
+            Controller->SetOverrideMaxReadStaleness(TDuration::Minutes(5));
         }
 
         void Execute(const ui64 destinationIdx, const std::vector<ui64>& sourceIdxs, const bool move, const NOlap::TSnapshot& snapshot, const std::set<ui64>& pathIdxs) {
-            Controller->SetOverrideReadTimeoutClean(TDuration::Seconds(1));
+            Controller->SetOverrideMaxReadStaleness(TDuration::Seconds(1));
             AFL_VERIFY(destinationIdx < ShardIds.size());
             const ui64 destination = ShardIds[destinationIdx];
             std::vector<ui64> sources;
@@ -198,7 +198,7 @@ Y_UNIT_TEST_SUITE(KqpOlapBlobsSharing) {
             CSTransferStatus->Reset();
             AFL_VERIFY(!Controller->IsTrivialLinks());
             Controller->CheckInvariants();
-            Controller->SetOverrideReadTimeoutClean(TDuration::Minutes(5));
+            Controller->SetOverrideMaxReadStaleness(TDuration::Minutes(5));
         }
     };
     Y_UNIT_TEST(BlobsSharingSplit1_1) {
diff --git a/ydb/core/kqp/ut/olap/write_ut.cpp b/ydb/core/kqp/ut/olap/write_ut.cpp
index 0784cfa235af..c339990668bd 100644
--- a/ydb/core/kqp/ut/olap/write_ut.cpp
+++ b/ydb/core/kqp/ut/olap/write_ut.cpp
@@ -251,7 +251,7 @@ Y_UNIT_TEST_SUITE(KqpOlapWrite) {
                           .ExtractValueSync();
             UNIT_ASSERT_C(it.IsSuccess(), it.GetIssues().ToString());
         }
-        csController->SetOverrideReadTimeoutClean(TDuration::Zero());
+        csController->SetOverrideMaxReadStaleness(TDuration::Zero());
         csController->EnableBackground(NKikimr::NYDBTest::ICSController::EBackground::GC);
         {
             const TInstant start = TInstant::Now();
diff --git a/ydb/core/tx/columnshard/columnshard.cpp b/ydb/core/tx/columnshard/columnshard.cpp
index 0d5c5766c270..117efd69d2e7 100644
--- a/ydb/core/tx/columnshard/columnshard.cpp
+++ b/ydb/core/tx/columnshard/columnshard.cpp
@@ -200,11 +200,16 @@ void TColumnShard::Handle(TEvPrivate::TEvReadFinished::TPtr& ev, const TActorCon
 }
 
 void TColumnShard::Handle(TEvPrivate::TEvPingSnapshotsUsage::TPtr& /*ev*/, const TActorContext& ctx) {
-    if (auto writeTx =
-            InFlightReadsTracker.Ping(this, NYDBTest::TControllers::GetColumnShardController()->GetPingCheckPeriod(), TInstant::Now())) {
+    const TDuration stalenessLivetime = NYDBTest::TControllers::GetColumnShardController()->GetMaxReadStaleness();
+    const TDuration stalenessInMem = NYDBTest::TControllers::GetColumnShardController()->GetMaxReadStalenessInMem();
+    const TDuration usedLivetime = NYDBTest::TControllers::GetColumnShardController()->GetUsedSnapshotLivetime();
+    AFL_VERIFY(usedLivetime < stalenessInMem || (stalenessInMem == usedLivetime && usedLivetime == TDuration::Zero()))("used", usedLivetime)(
+                                                "staleness", stalenessInMem);
+    const TDuration ping = 0.3 * std::min(stalenessInMem - usedLivetime, stalenessLivetime - stalenessInMem);
+    if (auto writeTx = InFlightReadsTracker.Ping(this, stalenessInMem, usedLivetime, TInstant::Now())) {
         Execute(writeTx.release(), ctx);
     }
-    ctx.Schedule(0.3 * GetMaxReadStaleness(), new TEvPrivate::TEvPingSnapshotsUsage());
+    ctx.Schedule(NYDBTest::TControllers::GetColumnShardController()->GetStalenessLivetimePing(ping), new TEvPrivate::TEvPingSnapshotsUsage());
 }
 
 void TColumnShard::Handle(TEvPrivate::TEvPeriodicWakeup::TPtr& ev, const TActorContext& ctx) {
diff --git a/ydb/core/tx/columnshard/columnshard_impl.cpp b/ydb/core/tx/columnshard/columnshard_impl.cpp
index 3821f0229993..5e1244cf1bf1 100644
--- a/ydb/core/tx/columnshard/columnshard_impl.cpp
+++ b/ydb/core/tx/columnshard/columnshard_impl.cpp
@@ -194,7 +194,7 @@ ui64 TColumnShard::GetOutdatedStep() const {
 }
 
 NOlap::TSnapshot TColumnShard::GetMinReadSnapshot() const {
-    ui64 delayMillisec = GetMaxReadStaleness().MilliSeconds();
+    ui64 delayMillisec = NYDBTest::TControllers::GetColumnShardController()->GetMaxReadStaleness().MilliSeconds();
     ui64 passedStep = GetOutdatedStep();
     ui64 minReadStep = (passedStep > delayMillisec ? passedStep - delayMillisec : 0);
 
@@ -1600,8 +1600,4 @@ const NKikimr::NColumnShard::NTiers::TManager* TColumnShard::GetTierManagerPoint
     return Tiers->GetManagerOptional(tierId);
 }
 
-TDuration TColumnShard::GetMaxReadStaleness() {
-    return NYDBTest::TControllers::GetColumnShardController()->GetReadTimeoutClean();
-}
-
 } // namespace NKikimr::NColumnShard
diff --git a/ydb/core/tx/columnshard/columnshard_impl.h b/ydb/core/tx/columnshard/columnshard_impl.h
index 844a3e20b80c..1c3f6343ecfc 100644
--- a/ydb/core/tx/columnshard/columnshard_impl.h
+++ b/ydb/core/tx/columnshard/columnshard_impl.h
@@ -536,7 +536,6 @@ class TColumnShard: public TActor<TColumnShard>, public NTabletFlatExecutor::TTa
     TLimits Limits;
     NOlap::TNormalizationController NormalizerController;
     NDataShard::TSysLocks SysLocks;
-    static TDuration GetMaxReadStaleness();
 
     void TryRegisterMediatorTimeCast();
     void UnregisterMediatorTimeCast();
diff --git a/ydb/core/tx/columnshard/hooks/abstract/abstract.h b/ydb/core/tx/columnshard/hooks/abstract/abstract.h
index 28470aca8bda..a747c5a5837a 100644
--- a/ydb/core/tx/columnshard/hooks/abstract/abstract.h
+++ b/ydb/core/tx/columnshard/hooks/abstract/abstract.h
@@ -61,6 +61,9 @@ class ICSController {
     };
 
 protected:
+    virtual std::optional<TDuration> DoGetStalenessLivetimePing() const {
+        return {};
+    }
     virtual void DoOnTabletInitCompleted(const ::NKikimr::NColumnShard::TColumnShard& /*shard*/) {
         return;
     }
@@ -85,7 +88,7 @@ class ICSController {
     virtual void DoOnDataSharingStarted(const ui64 /*tabletId*/, const TString& /*sessionId*/) {
     }
 
-    virtual TDuration DoGetPingCheckPeriod(const TDuration defaultValue) const {
+    virtual TDuration DoGetUsedSnapshotLivetime(const TDuration defaultValue) const {
         return defaultValue;
     }
     virtual TDuration DoGetOverridenGCPeriod(const TDuration defaultValue) const {
@@ -109,7 +112,7 @@ class ICSController {
     virtual ui64 DoGetSmallPortionSizeDetector(const ui64 defaultValue) const {
         return defaultValue;
     }
-    virtual TDuration DoGetReadTimeoutClean(const TDuration defaultValue) const {
+    virtual TDuration DoGetMaxReadStaleness(const TDuration defaultValue) const {
         return defaultValue;
     }
     virtual TDuration DoGetGuaranteeIndexationInterval(const TDuration defaultValue) const {
@@ -158,9 +161,13 @@ class ICSController {
     }
     virtual bool CheckPortionForEvict(const NOlap::TPortionInfo& portion) const;
 
-    TDuration GetPingCheckPeriod() const {
-        const TDuration defaultValue = 0.6 * GetReadTimeoutClean();
-        return DoGetPingCheckPeriod(defaultValue);
+    TDuration GetStalenessLivetimePing(const TDuration defValue) const {
+        const auto val = DoGetStalenessLivetimePing();
+        if (!val || defValue < *val) {
+            return defValue;
+        } else {
+            return *val;
+        }
     }
 
     virtual bool IsBackgroundEnabled(const EBackground /*id*/) const {
@@ -261,9 +268,16 @@ class ICSController {
     }
     virtual void OnIndexSelectProcessed(const std::optional<bool> /*result*/) {
     }
-    TDuration GetReadTimeoutClean() const {
+    TDuration GetMaxReadStaleness() const {
         const TDuration defaultValue = TDuration::MilliSeconds(GetConfig().GetMaxReadStaleness_ms());
-        return DoGetReadTimeoutClean(defaultValue);
+        return DoGetMaxReadStaleness(defaultValue);
+    }
+    TDuration GetMaxReadStalenessInMem() const {
+        return 0.9 * GetMaxReadStaleness();
+    }
+    TDuration GetUsedSnapshotLivetime() const {
+        const TDuration defaultValue = 0.6 * GetMaxReadStaleness();
+        return DoGetUsedSnapshotLivetime(defaultValue);
     }
     virtual EOptimizerCompactionWeightControl GetCompactionControl() const {
         return EOptimizerCompactionWeightControl::Force;
diff --git a/ydb/core/tx/columnshard/hooks/testing/controller.h b/ydb/core/tx/columnshard/hooks/testing/controller.h
index d57470a0a93b..af375a612caf 100644
--- a/ydb/core/tx/columnshard/hooks/testing/controller.h
+++ b/ydb/core/tx/columnshard/hooks/testing/controller.h
@@ -12,7 +12,8 @@ namespace NKikimr::NYDBTest::NColumnShard {
 class TController: public TReadOnlyController {
 private:
     using TBase = TReadOnlyController;
-    YDB_ACCESSOR_DEF(std::optional<TDuration>, OverrideRequestsTracePingCheckPeriod);
+    YDB_ACCESSOR_DEF(std::optional<TDuration>, OverrideUsedSnapshotLivetime);
+    YDB_ACCESSOR_DEF(std::optional<TDuration>, OverrideStalenessLivetimePing);
     YDB_ACCESSOR_DEF(std::optional<TDuration>, OverrideLagForCompactionBeforeTierings);
     YDB_ACCESSOR(std::optional<TDuration>, OverrideGuaranteeIndexationInterval, TDuration::Zero());
     YDB_ACCESSOR(std::optional<TDuration>, OverridePeriodicWakeupActivationPeriod, std::nullopt);
@@ -21,7 +22,7 @@ class TController: public TReadOnlyController {
     YDB_ACCESSOR(std::optional<TDuration>, OverrideOptimizerFreshnessCheckDuration, TDuration::Zero());
     YDB_ACCESSOR_DEF(std::optional<TDuration>, OverrideCompactionActualizationLag);
     YDB_ACCESSOR_DEF(std::optional<TDuration>, OverrideTasksActualizationLag);
-    YDB_ACCESSOR_DEF(std::optional<TDuration>, OverrideReadTimeoutClean);
+    YDB_ACCESSOR_DEF(std::optional<TDuration>, OverrideMaxReadStaleness);
     YDB_ACCESSOR(std::optional<ui64>, OverrideMemoryLimitForPortionReading, 100);
     YDB_ACCESSOR_DEF(std::optional<NKikimrProto::EReplyStatus>, OverrideBlobPutResultOnWriteValue);
 
@@ -142,10 +143,12 @@ class TController: public TReadOnlyController {
         return OverrideLagForCompactionBeforeTierings.value_or(def);
     }
 
-    virtual TDuration DoGetPingCheckPeriod(const TDuration def) const override {
-        return OverrideRequestsTracePingCheckPeriod.value_or(def);
+    virtual TDuration DoGetUsedSnapshotLivetime(const TDuration def) const override {
+        return OverrideUsedSnapshotLivetime.value_or(def);
+    }
+    virtual std::optional<TDuration> DoGetStalenessLivetimePing() const override {
+        return OverrideStalenessLivetimePing;
     }
-
     virtual TDuration DoGetCompactionActualizationLag(const TDuration def) const override {
         return OverrideCompactionActualizationLag.value_or(def);
     }
@@ -180,8 +183,8 @@ class TController: public TReadOnlyController {
     virtual TDuration DoGetOptimizerFreshnessCheckDuration(const TDuration defaultValue) const override {
         return OverrideOptimizerFreshnessCheckDuration.value_or(defaultValue);
     }
-    virtual TDuration DoGetReadTimeoutClean(const TDuration def) const override {
-        return OverrideReadTimeoutClean.value_or(def);
+    virtual TDuration DoGetMaxReadStaleness(const TDuration def) const override {
+        return OverrideMaxReadStaleness.value_or(def);
     }
     virtual ui64 DoGetReduceMemoryIntervalLimit(const ui64 def) const override {
         return OverrideReduceMemoryIntervalLimit.value_or(def);
diff --git a/ydb/core/tx/columnshard/inflight_request_tracker.cpp b/ydb/core/tx/columnshard/inflight_request_tracker.cpp
index 6b7830b26cb0..ea5a7bc68e17 100644
--- a/ydb/core/tx/columnshard/inflight_request_tracker.cpp
+++ b/ydb/core/tx/columnshard/inflight_request_tracker.cpp
@@ -19,9 +19,7 @@ NOlap::NReader::TReadMetadataBase::TConstPtr TInFlightReadsTracker::ExtractInFli
         {
             auto it = SnapshotsLive.find(readMetaBase->GetRequestSnapshot());
             AFL_VERIFY(it != SnapshotsLive.end());
-            if (it->second.DelRequest(cookie, now)) {
-                SnapshotsLive.erase(it);
-            }
+            Y_UNUSED(it->second.DelRequest(cookie, now));
         }
 
         if (NOlap::NReader::NPlain::TReadMetadata::TConstPtr readMeta =
@@ -93,27 +91,29 @@ class TTransactionSavePersistentSnapshots: public NOlap::NDataSharing::TExtended
 }   // namespace
 
 std::unique_ptr<NTabletFlatExecutor::ITransaction> TInFlightReadsTracker::Ping(
-    TColumnShard* self, const TDuration critDuration, const TInstant now) {
+    TColumnShard* self, const TDuration stalenessInMem, const TDuration usedSnapshotLivetime, const TInstant now) {
     std::set<NOlap::TSnapshot> snapshotsToSave;
-    std::set<NOlap::TSnapshot> snapshotsToFree;
+    std::set<NOlap::TSnapshot> snapshotsToFreeInDB;
+    std::set<NOlap::TSnapshot> snapshotsToFreeInMem;
     for (auto&& i : SnapshotsLive) {
-        if (i.second.Ping(critDuration, now)) {
+        if (i.second.IsExpired(usedSnapshotLivetime, now)) {
             if (i.second.GetIsLock()) {
-                Counters->OnSnapshotLocked();
-                snapshotsToSave.emplace(i.first);
-            } else {
                 Counters->OnSnapshotUnlocked();
-                snapshotsToFree.emplace(i.first);
+                snapshotsToFreeInDB.emplace(i.first);
             }
+            snapshotsToFreeInMem.emplace(i.first);
+        } else if (i.second.CheckToLock(stalenessInMem, usedSnapshotLivetime, now)) {
+            Counters->OnSnapshotLocked();
+            snapshotsToSave.emplace(i.first);
         }
     }
-    for (auto&& i : snapshotsToFree) {
+    for (auto&& i : snapshotsToFreeInMem) {
         SnapshotsLive.erase(i);
     }
     Counters->OnSnapshotsInfo(SnapshotsLive.size(), GetSnapshotToClean());
-    if (snapshotsToFree.size() || snapshotsToSave.size()) {
-        NYDBTest::TControllers::GetColumnShardController()->OnRequestTracingChanges(snapshotsToSave, snapshotsToFree);
-        return std::make_unique<TTransactionSavePersistentSnapshots>(self, std::move(snapshotsToSave), std::move(snapshotsToFree));
+    if (snapshotsToFreeInDB.size() || snapshotsToSave.size()) {
+        NYDBTest::TControllers::GetColumnShardController()->OnRequestTracingChanges(snapshotsToSave, snapshotsToFreeInMem);
+        return std::make_unique<TTransactionSavePersistentSnapshots>(self, std::move(snapshotsToSave), std::move(snapshotsToFreeInDB));
     } else {
         return nullptr;
     }
diff --git a/ydb/core/tx/columnshard/inflight_request_tracker.h b/ydb/core/tx/columnshard/inflight_request_tracker.h
index 0aeec5acddbe..51de0a26795f 100644
--- a/ydb/core/tx/columnshard/inflight_request_tracker.h
+++ b/ydb/core/tx/columnshard/inflight_request_tracker.h
@@ -17,7 +17,6 @@ using NOlap::IBlobInUseTracker;
 class TSnapshotLiveInfo {
 private:
     const NOlap::TSnapshot Snapshot;
-    std::optional<TInstant> LastPingInstant;
     std::optional<TInstant> LastRequestFinishedInstant;
     THashSet<ui32> Requests;
     YDB_READONLY(bool, IsLock, false);
@@ -48,22 +47,32 @@ class TSnapshotLiveInfo {
 
     static TSnapshotLiveInfo BuildFromDatabase(const NOlap::TSnapshot& reqSnapshot) {
         TSnapshotLiveInfo result(reqSnapshot);
-        result.LastPingInstant = TInstant::Now();
-        result.LastRequestFinishedInstant = result.LastPingInstant;
+        result.LastRequestFinishedInstant = TInstant::Now();
         result.IsLock = true;
         return result;
     }
 
-    bool Ping(const TDuration critDuration, const TInstant now) {
-        LastPingInstant = now;
-        if (Requests.empty()) {
-            AFL_VERIFY(LastRequestFinishedInstant);
-            if (critDuration < *LastPingInstant - *LastRequestFinishedInstant && IsLock) {
-                IsLock = false;
+    bool IsExpired(const TDuration critDuration, const TInstant now) const {
+        if (Requests.size()) {
+            return false;
+        }
+        AFL_VERIFY(LastRequestFinishedInstant);
+        return critDuration < now - *LastRequestFinishedInstant;
+    }
+
+    bool CheckToLock(const TDuration snapshotLivetime, const TDuration usedSnapshotGuaranteeLivetime, const TInstant now) {
+        if (IsLock) {
+            return false;
+        }
+
+        if (Requests.size()) {
+            if (now + usedSnapshotGuaranteeLivetime > Snapshot.GetPlanInstant() + snapshotLivetime) {
+                IsLock = true;
                 return true;
             }
         } else {
-            if (critDuration < *LastPingInstant - Snapshot.GetPlanInstant() && !IsLock) {
+            AFL_VERIFY(LastRequestFinishedInstant);
+            if (*LastRequestFinishedInstant + usedSnapshotGuaranteeLivetime > Snapshot.GetPlanInstant() + snapshotLivetime) {
                 IsLock = true;
                 return true;
             }
@@ -88,7 +97,8 @@ class TInFlightReadsTracker {
 
     bool LoadFromDatabase(NTable::TDatabase& db);
 
-    [[nodiscard]] std::unique_ptr<NTabletFlatExecutor::ITransaction> Ping(TColumnShard* self, const TDuration critDuration, const TInstant now);
+    [[nodiscard]] std::unique_ptr<NTabletFlatExecutor::ITransaction> Ping(
+        TColumnShard* self, const TDuration stalenessInMem, const TDuration usedSnapshotLivetime, const TInstant now);
 
     // Returns a unique cookie associated with this request
     [[nodiscard]] ui64 AddInFlightRequest(
diff --git a/ydb/core/tx/columnshard/ut_rw/ut_columnshard_read_write.cpp b/ydb/core/tx/columnshard/ut_rw/ut_columnshard_read_write.cpp
index 25e1de8038e7..262fd7be633d 100644
--- a/ydb/core/tx/columnshard/ut_rw/ut_columnshard_read_write.cpp
+++ b/ydb/core/tx/columnshard/ut_rw/ut_columnshard_read_write.cpp
@@ -552,7 +552,7 @@ void TestWriteReadDup(const TestTableDescription& table = {}) {
 void TestWriteRead(bool reboots, const TestTableDescription& table = {}, TString codec = "") {
     auto csControllerGuard = NKikimr::NYDBTest::TControllers::RegisterCSControllerGuard<TDefaultTestsController>();
     csControllerGuard->DisableBackground(NKikimr::NYDBTest::ICSController::EBackground::Compaction);
-    csControllerGuard->SetOverrideReadTimeoutClean(TDuration::Max());
+    csControllerGuard->SetOverrideMaxReadStaleness(TDuration::Max());
     TTestBasicRuntime runtime;
     TTester::Setup(runtime);
 
@@ -2654,7 +2654,8 @@ Y_UNIT_TEST_SUITE(TColumnShardTestReadWrite) {
             PlanCommit(runtime, sender, planStep, txId);
         }
         UNIT_ASSERT_EQUAL(cleanupsHappened, 0);
-        csDefaultControllerGuard->SetOverrideRequestsTracePingCheckPeriod(TDuration::Zero());
+        csDefaultControllerGuard->SetOverrideStalenessLivetimePing(TDuration::Zero());
+        csDefaultControllerGuard->SetOverrideUsedSnapshotLivetime(TDuration::Zero());
         {
             auto read = std::make_unique<NColumnShard::TEvPrivate::TEvPingSnapshotsUsage>();
             ForwardToTablet(runtime, TTestTxConfig::TxTablet0, sender, read.release());