diff --git a/src/Storages/IStorage.h b/src/Storages/IStorage.h
index 3cf26d218cd..5b49e1cfd4c 100644
--- a/src/Storages/IStorage.h
+++ b/src/Storages/IStorage.h
@@ -449,7 +449,7 @@ public:
     }
 
     /// If it is possible to quickly determine exact number of bytes for the table on storage:
-    /// - memory (approximated)
+    /// - memory (approximated, resident)
     /// - disk (compressed)
     ///
     /// Used for:
@@ -457,6 +457,10 @@ public:
     //
     /// Does not takes underlying Storage (if any) into account
     /// (since for Buffer we still need to know how much bytes it uses).
+    ///
+    /// Memory part should be estimated as a resident memory size.
+    /// In particular, alloctedBytes() is preferable over bytes()
+    /// when considering in-memory blocks.
     virtual std::optional<UInt64> totalBytes() const
     {
         return {};
diff --git a/src/Storages/StorageBuffer.cpp b/src/Storages/StorageBuffer.cpp
index e0bd19feba9..85b61dd34f9 100644
--- a/src/Storages/StorageBuffer.cpp
+++ b/src/Storages/StorageBuffer.cpp
@@ -797,7 +797,7 @@ std::optional<UInt64> StorageBuffer::totalBytes() const
     for (const auto & buffer : buffers)
     {
         std::lock_guard lock(buffer.mutex);
-        bytes += buffer.data.bytes();
+        bytes += buffer.data.allocatedBytes();
     }
     return bytes;
 }
diff --git a/src/Storages/StorageMemory.cpp b/src/Storages/StorageMemory.cpp
index 44413caaa57..3a10b2c7e7d 100644
--- a/src/Storages/StorageMemory.cpp
+++ b/src/Storages/StorageMemory.cpp
@@ -169,7 +169,7 @@ std::optional<UInt64> StorageMemory::totalBytes() const
     UInt64 bytes = 0;
     std::lock_guard lock(mutex);
     for (const auto & buffer : data)
-        bytes += buffer.bytes();
+        bytes += buffer.allocatedBytes();
     return bytes;
 }
 
diff --git a/tests/queries/0_stateless/00753_system_columns_and_system_tables.reference b/tests/queries/0_stateless/00753_system_columns_and_system_tables.reference
index e84e610bb93..1d1177ba447 100644
--- a/tests/queries/0_stateless/00753_system_columns_and_system_tables.reference
+++ b/tests/queries/0_stateless/00753_system_columns_and_system_tables.reference
@@ -29,7 +29,7 @@ Check total_bytes/total_rows for TinyLog
 \N	\N
 Check total_bytes/total_rows for Memory
 0	0
-2	1
+64	1
 Check total_bytes/total_rows for Buffer
 0	0
-100	50
+256	50