diff --git a/src/Formats/TemporaryFileStream.cpp b/src/Formats/TemporaryFileStream.cpp
index e8dc832dbe1..f4c66b67a45 100644
--- a/src/Formats/TemporaryFileStream.cpp
+++ b/src/Formats/TemporaryFileStream.cpp
@@ -39,10 +39,7 @@ TemporaryFileStream::Stat TemporaryFileStream::write(const std::string & path, c
         output.write(block);
 
     compressed_buf.finalize();
-    output.flush();
-    file_buf.next();
-
-    return Stat{compressed_buf.count(), file_buf.count()};
+    return Stat{compressed_buf.getCompressedBytes(), compressed_buf.getUncompressedBytes()};
 }
 
 }
diff --git a/src/Formats/TemporaryFileStream.h b/src/Formats/TemporaryFileStream.h
index f61d928d204..e858da1dc33 100644
--- a/src/Formats/TemporaryFileStream.h
+++ b/src/Formats/TemporaryFileStream.h
@@ -14,8 +14,8 @@ struct TemporaryFileStream
 {
     struct Stat
     {
-        size_t uncompressed_bytes = 0;
         size_t compressed_bytes = 0;
+        size_t uncompressed_bytes = 0;
     };
 
     ReadBufferFromFile file_in;
diff --git a/src/Processors/Transforms/MergeSortingTransform.cpp b/src/Processors/Transforms/MergeSortingTransform.cpp
index 7d632654964..001c33baa4a 100644
--- a/src/Processors/Transforms/MergeSortingTransform.cpp
+++ b/src/Processors/Transforms/MergeSortingTransform.cpp
@@ -63,7 +63,7 @@ public:
             compressed_buf_out.next();
             file_buf_out.next();
 
-            updateStat();
+            auto stat = updateWriteStat();
 
             LOG_INFO(log, "Done writing part of data into temporary file {}, compressed {}, uncompressed {} ",
                 path, ReadableSize(static_cast<double>(stat.compressed_size)), ReadableSize(static_cast<double>(stat.uncompressed_size)));
@@ -90,16 +90,22 @@ public:
     }
 
 private:
-    void updateStat()
+    struct Stat
     {
-        stat.compressed_size = file_buf_out.count();
-        stat.uncompressed_size = compressed_buf_out.count();
+        size_t compressed_size = 0;
+        size_t uncompressed_size = 0;
+    };
 
-        ProfileEvents::increment(ProfileEvents::ExternalProcessingCompressedBytesTotal, stat.compressed_size);
-        ProfileEvents::increment(ProfileEvents::ExternalProcessingUncompressedBytesTotal, stat.uncompressed_size);
+    Stat updateWriteStat()
+    {
+        Stat res{compressed_buf_out.getCompressedBytes(), compressed_buf_out.getUncompressedBytes()};
 
-        ProfileEvents::increment(ProfileEvents::ExternalSortCompressedBytes, stat.compressed_size);
-        ProfileEvents::increment(ProfileEvents::ExternalSortUncompressedBytes, stat.uncompressed_size);
+        ProfileEvents::increment(ProfileEvents::ExternalProcessingCompressedBytesTotal, res.compressed_size);
+        ProfileEvents::increment(ProfileEvents::ExternalProcessingUncompressedBytesTotal, res.uncompressed_size);
+
+        ProfileEvents::increment(ProfileEvents::ExternalSortCompressedBytes, res.compressed_size);
+        ProfileEvents::increment(ProfileEvents::ExternalSortUncompressedBytes, res.uncompressed_size);
+        return res;
     }
 
     Poco::Logger * log;
@@ -111,12 +117,6 @@ private:
     std::unique_ptr<ReadBufferFromFile> file_in;
     std::unique_ptr<CompressedReadBuffer> compressed_in;
     std::unique_ptr<NativeReader> block_in;
-
-    struct
-    {
-        size_t compressed_size = 0;
-        size_t uncompressed_size = 0;
-    } stat;
 };
 
 MergeSortingTransform::MergeSortingTransform(