diff --git a/src/Common/MemoryTracker.cpp b/src/Common/MemoryTracker.cpp
index d037142fbfb..a584885cf0f 100644
--- a/src/Common/MemoryTracker.cpp
+++ b/src/Common/MemoryTracker.cpp
@@ -24,8 +24,8 @@ namespace
 ///
 /// - when it is explicitly blocked with LockExceptionInThread
 ///
-/// - to avoid std::terminate(), when stack unwinding is current in progress in
-///   this thread.
+/// - to avoid std::terminate(), when stack unwinding is currently in progress
+///   in this thread.
 ///
 ///   NOTE: that since C++11 destructor marked with noexcept by default, and
 ///   this means that any throw from destructor (that is not marked with
diff --git a/src/Common/ZooKeeper/IKeeper.h b/src/Common/ZooKeeper/IKeeper.h
index 9d4a2ebb16a..c53ea60ec7c 100644
--- a/src/Common/ZooKeeper/IKeeper.h
+++ b/src/Common/ZooKeeper/IKeeper.h
@@ -331,7 +331,7 @@ public:
 class IKeeper
 {
 public:
-    virtual ~IKeeper() {}
+    virtual ~IKeeper() = default;
 
     /// If expired, you can only destroy the object. All other methods will throw exception.
     virtual bool isExpired() const = 0;
diff --git a/src/Compression/CompressedWriteBuffer.cpp b/src/Compression/CompressedWriteBuffer.cpp
index 02f418dcdf7..8d146e8de23 100644
--- a/src/Compression/CompressedWriteBuffer.cpp
+++ b/src/Compression/CompressedWriteBuffer.cpp
@@ -8,6 +8,7 @@
 #include <Compression/CompressionFactory.h>
 
 #include <Common/MemorySanitizer.h>
+#include <Common/MemoryTracker.h>
 
 
 namespace DB
@@ -49,14 +50,9 @@ CompressedWriteBuffer::CompressedWriteBuffer(
 
 CompressedWriteBuffer::~CompressedWriteBuffer()
 {
-    try
-    {
-        next();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+    next();
 }
 
 }
diff --git a/src/DataStreams/IBlockOutputStream.h b/src/DataStreams/IBlockOutputStream.h
index 4cc1257e955..79c13b6fa47 100644
--- a/src/DataStreams/IBlockOutputStream.h
+++ b/src/DataStreams/IBlockOutputStream.h
@@ -57,7 +57,7 @@ public:
       */
     virtual std::string getContentType() const { return "text/plain; charset=UTF-8"; }
 
-    virtual ~IBlockOutputStream() {}
+    virtual ~IBlockOutputStream() = default;
 
     /** Don't let to alter table while instance of stream is alive.
       */
diff --git a/src/IO/AsynchronousWriteBuffer.h b/src/IO/AsynchronousWriteBuffer.h
index 74b5804691b..8c44f8c7d4a 100644
--- a/src/IO/AsynchronousWriteBuffer.h
+++ b/src/IO/AsynchronousWriteBuffer.h
@@ -1,10 +1,8 @@
 #pragma once
 
-#include <math.h>
-
 #include <vector>
-
 #include <Common/ThreadPool.h>
+#include <Common/MemoryTracker.h>
 #include <IO/WriteBuffer.h>
 
 
@@ -53,18 +51,14 @@ public:
 
     ~AsynchronousWriteBuffer() override
     {
-        try
-        {
-            if (started)
-                pool.wait();
+        /// FIXME move final flush into the caller
+        MemoryTracker::LockExceptionInThread lock;
 
-            swapBuffers();
-            out.next();
-        }
-        catch (...)
-        {
-            tryLogCurrentException(__PRETTY_FUNCTION__);
-        }
+        if (started)
+            pool.wait();
+
+        swapBuffers();
+        out.next();
     }
 
     /// That is executed in a separate thread
diff --git a/src/IO/BrotliWriteBuffer.cpp b/src/IO/BrotliWriteBuffer.cpp
index e4e3713d379..d14c94ca43d 100644
--- a/src/IO/BrotliWriteBuffer.cpp
+++ b/src/IO/BrotliWriteBuffer.cpp
@@ -6,6 +6,8 @@
 #    include <IO/BrotliWriteBuffer.h>
 #    include <brotli/encode.h>
 
+#include <Common/MemoryTracker.h>
+
 namespace DB
 {
 
@@ -47,14 +49,9 @@ BrotliWriteBuffer::BrotliWriteBuffer(std::unique_ptr<WriteBuffer> out_, int comp
 
 BrotliWriteBuffer::~BrotliWriteBuffer()
 {
-    try
-    {
-        finish();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+    finish();
 }
 
 void BrotliWriteBuffer::nextImpl()
diff --git a/src/IO/HexWriteBuffer.cpp b/src/IO/HexWriteBuffer.cpp
index d7b8a993ce5..4e3403ba74b 100644
--- a/src/IO/HexWriteBuffer.cpp
+++ b/src/IO/HexWriteBuffer.cpp
@@ -1,6 +1,6 @@
 #include <common/types.h>
 #include <Common/hex.h>
-#include <Common/Exception.h>
+#include <Common/MemoryTracker.h>
 #include <IO/HexWriteBuffer.h>
 
 
@@ -22,14 +22,9 @@ void HexWriteBuffer::nextImpl()
 
 HexWriteBuffer::~HexWriteBuffer()
 {
-    try
-    {
-        nextImpl();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+    nextImpl();
 }
 
 }
diff --git a/src/IO/IReadableWriteBuffer.h b/src/IO/IReadableWriteBuffer.h
index a02dd4e23cb..539825e3a85 100644
--- a/src/IO/IReadableWriteBuffer.h
+++ b/src/IO/IReadableWriteBuffer.h
@@ -17,7 +17,7 @@ struct IReadableWriteBuffer
         return getReadBufferImpl();
     }
 
-    virtual ~IReadableWriteBuffer() {}
+    virtual ~IReadableWriteBuffer() = default;
 
 protected:
 
diff --git a/src/IO/LZMADeflatingWriteBuffer.cpp b/src/IO/LZMADeflatingWriteBuffer.cpp
index e3051f1de65..5803bc1e9f1 100644
--- a/src/IO/LZMADeflatingWriteBuffer.cpp
+++ b/src/IO/LZMADeflatingWriteBuffer.cpp
@@ -1,4 +1,5 @@
 #include <IO/LZMADeflatingWriteBuffer.h>
+#include <Common/MemoryTracker.h>
 
 #if !defined(ARCADIA_BUILD)
 
@@ -48,16 +49,11 @@ LZMADeflatingWriteBuffer::LZMADeflatingWriteBuffer(
 
 LZMADeflatingWriteBuffer::~LZMADeflatingWriteBuffer()
 {
-    try
-    {
-        finish();
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
 
-        lzma_end(&lstr);
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    finish();
+    lzma_end(&lstr);
 }
 
 void LZMADeflatingWriteBuffer::nextImpl()
diff --git a/src/IO/WriteBufferFromFile.cpp b/src/IO/WriteBufferFromFile.cpp
index aeed4862fba..b3a63842326 100644
--- a/src/IO/WriteBufferFromFile.cpp
+++ b/src/IO/WriteBufferFromFile.cpp
@@ -3,6 +3,7 @@
 #include <errno.h>
 
 #include <Common/ProfileEvents.h>
+#include <Common/MemoryTracker.h>
 
 #include <IO/WriteBufferFromFile.h>
 #include <IO/WriteHelpers.h>
@@ -77,14 +78,10 @@ WriteBufferFromFile::~WriteBufferFromFile()
     if (fd < 0)
         return;
 
-    try
-    {
-        next();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+
+    next();
 
     ::close(fd);
 }
diff --git a/src/IO/WriteBufferFromFileDescriptor.cpp b/src/IO/WriteBufferFromFileDescriptor.cpp
index a59ae20c588..bfd874ee396 100644
--- a/src/IO/WriteBufferFromFileDescriptor.cpp
+++ b/src/IO/WriteBufferFromFileDescriptor.cpp
@@ -8,6 +8,7 @@
 #include <Common/ProfileEvents.h>
 #include <Common/CurrentMetrics.h>
 #include <Common/Stopwatch.h>
+#include <Common/MemoryTracker.h>
 
 #include <IO/WriteBufferFromFileDescriptor.h>
 #include <IO/WriteHelpers.h>
@@ -90,17 +91,15 @@ WriteBufferFromFileDescriptor::WriteBufferFromFileDescriptor(
 
 WriteBufferFromFileDescriptor::~WriteBufferFromFileDescriptor()
 {
-    try
+    if (fd < 0)
     {
-        if (fd >= 0)
-            next();
-        else
-            assert(!offset() && "attempt to write after close");
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
+        assert(!offset() && "attempt to write after close");
+        return;
     }
+
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+    next();
 }
 
 
diff --git a/src/IO/WriteBufferFromHTTPServerResponse.cpp b/src/IO/WriteBufferFromHTTPServerResponse.cpp
index 0f30f1352e3..fb9a6a99d2b 100644
--- a/src/IO/WriteBufferFromHTTPServerResponse.cpp
+++ b/src/IO/WriteBufferFromHTTPServerResponse.cpp
@@ -7,6 +7,7 @@
 #include <Common/Exception.h>
 #include <Common/NetException.h>
 #include <Common/Stopwatch.h>
+#include <Common/MemoryTracker.h>
 
 #if !defined(ARCADIA_BUILD)
 #    include <Common/config.h>
@@ -206,14 +207,9 @@ void WriteBufferFromHTTPServerResponse::finalize()
 
 WriteBufferFromHTTPServerResponse::~WriteBufferFromHTTPServerResponse()
 {
-    try
-    {
-        finalize();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+    finalize();
 }
 
 }
diff --git a/src/IO/WriteBufferFromOStream.cpp b/src/IO/WriteBufferFromOStream.cpp
index 2c45a21a0a3..cf731934c93 100644
--- a/src/IO/WriteBufferFromOStream.cpp
+++ b/src/IO/WriteBufferFromOStream.cpp
@@ -1,5 +1,5 @@
 #include <IO/WriteBufferFromOStream.h>
-#include <Common/Exception.h>
+#include <Common/MemoryTracker.h>
 
 
 namespace DB
@@ -42,14 +42,9 @@ WriteBufferFromOStream::WriteBufferFromOStream(
 
 WriteBufferFromOStream::~WriteBufferFromOStream()
 {
-    try
-    {
-        next();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+    next();
 }
 
 }
diff --git a/src/IO/WriteBufferFromPocoSocket.cpp b/src/IO/WriteBufferFromPocoSocket.cpp
index c05dc11e330..284fa5dbd97 100644
--- a/src/IO/WriteBufferFromPocoSocket.cpp
+++ b/src/IO/WriteBufferFromPocoSocket.cpp
@@ -5,6 +5,7 @@
 #include <Common/Exception.h>
 #include <Common/NetException.h>
 #include <Common/Stopwatch.h>
+#include <Common/MemoryTracker.h>
 
 
 namespace ProfileEvents
@@ -70,14 +71,9 @@ WriteBufferFromPocoSocket::WriteBufferFromPocoSocket(Poco::Net::Socket & socket_
 
 WriteBufferFromPocoSocket::~WriteBufferFromPocoSocket()
 {
-    try
-    {
-        next();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+    next();
 }
 
 }
diff --git a/src/IO/WriteBufferFromS3.cpp b/src/IO/WriteBufferFromS3.cpp
index 09aabb1b21d..a6ec60b295f 100644
--- a/src/IO/WriteBufferFromS3.cpp
+++ b/src/IO/WriteBufferFromS3.cpp
@@ -4,6 +4,7 @@
 
 #    include <IO/WriteBufferFromS3.h>
 #    include <IO/WriteHelpers.h>
+#    include <Common/MemoryTracker.h>
 
 #    include <aws/s3/S3Client.h>
 #    include <aws/s3/model/CreateMultipartUploadRequest.h>
@@ -78,6 +79,8 @@ void WriteBufferFromS3::nextImpl()
 
 void WriteBufferFromS3::finalize()
 {
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
     finalizeImpl();
 }
 
@@ -104,14 +107,7 @@ void WriteBufferFromS3::finalizeImpl()
 
 WriteBufferFromS3::~WriteBufferFromS3()
 {
-    try
-    {
-        finalizeImpl();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    finalizeImpl();
 }
 
 void WriteBufferFromS3::createMultipartUpload()
diff --git a/src/IO/WriteBufferFromVector.h b/src/IO/WriteBufferFromVector.h
index 2a9810f3461..1dcf2c3f327 100644
--- a/src/IO/WriteBufferFromVector.h
+++ b/src/IO/WriteBufferFromVector.h
@@ -3,6 +3,7 @@
 #include <vector>
 
 #include <IO/WriteBuffer.h>
+#include <Common/MemoryTracker.h>
 
 
 namespace DB
@@ -93,14 +94,9 @@ public:
 
     ~WriteBufferFromVector() override
     {
-        try
-        {
-            finalize();
-        }
-        catch (...)
-        {
-            tryLogCurrentException(__PRETTY_FUNCTION__);
-        }
+        /// FIXME move final flush into the caller
+        MemoryTracker::LockExceptionInThread lock;
+        finalize();
     }
 };
 
diff --git a/src/IO/WriteBufferValidUTF8.cpp b/src/IO/WriteBufferValidUTF8.cpp
index f1f04e9805b..1071ac1078d 100644
--- a/src/IO/WriteBufferValidUTF8.cpp
+++ b/src/IO/WriteBufferValidUTF8.cpp
@@ -1,5 +1,6 @@
 #include <Poco/UTF8Encoding.h>
 #include <IO/WriteBufferValidUTF8.h>
+#include <Common/MemoryTracker.h>
 #include <common/types.h>
 
 #ifdef __SSE2__
@@ -136,14 +137,9 @@ void WriteBufferValidUTF8::finish()
 
 WriteBufferValidUTF8::~WriteBufferValidUTF8()
 {
-    try
-    {
-        finish();
-    }
-    catch (...)
-    {
-        tryLogCurrentException(__PRETTY_FUNCTION__);
-    }
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+    finish();
 }
 
 }
diff --git a/src/IO/ZlibDeflatingWriteBuffer.cpp b/src/IO/ZlibDeflatingWriteBuffer.cpp
index 8efe96877e4..4b838ac6d0a 100644
--- a/src/IO/ZlibDeflatingWriteBuffer.cpp
+++ b/src/IO/ZlibDeflatingWriteBuffer.cpp
@@ -1,5 +1,7 @@
 #include <IO/ZlibDeflatingWriteBuffer.h>
 #include <Common/MemorySanitizer.h>
+#include <Common/MemoryTracker.h>
+#include <Common/Exception.h>
 
 
 namespace DB
@@ -46,16 +48,21 @@ ZlibDeflatingWriteBuffer::ZlibDeflatingWriteBuffer(
 
 ZlibDeflatingWriteBuffer::~ZlibDeflatingWriteBuffer()
 {
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+
+    finish();
+
     try
     {
-        finish();
-
         int rc = deflateEnd(&zstr);
         if (rc != Z_OK)
             throw Exception(std::string("deflateEnd failed: ") + zError(rc), ErrorCodes::ZLIB_DEFLATE_FAILED);
     }
     catch (...)
     {
+        /// It is OK not to terminate under an error from deflateEnd()
+        /// since all data already written to the stream.
         tryLogCurrentException(__PRETTY_FUNCTION__);
     }
 }
diff --git a/src/IO/ZstdDeflatingWriteBuffer.cpp b/src/IO/ZstdDeflatingWriteBuffer.cpp
index df28820e382..9b79d5ae513 100644
--- a/src/IO/ZstdDeflatingWriteBuffer.cpp
+++ b/src/IO/ZstdDeflatingWriteBuffer.cpp
@@ -1,4 +1,6 @@
 #include <IO/ZstdDeflatingWriteBuffer.h>
+#include <Common/MemoryTracker.h>
+#include <Common/Exception.h>
 
 namespace DB
 {
@@ -28,14 +30,22 @@ ZstdDeflatingWriteBuffer::ZstdDeflatingWriteBuffer(
 
 ZstdDeflatingWriteBuffer::~ZstdDeflatingWriteBuffer()
 {
+    /// FIXME move final flush into the caller
+    MemoryTracker::LockExceptionInThread lock;
+
+    finish();
+
     try
     {
-        finish();
-
-        ZSTD_freeCCtx(cctx);
+        int err = ZSTD_freeCCtx(cctx);
+        /// This is just in case, since it is impossible to get an error by using this wrapper.
+        if (unlikely(err))
+            throw Exception(ErrorCodes::ZSTD_ENCODER_FAILED, "ZSTD_freeCCtx failed: error code: {}; zstd version: {}", err, ZSTD_VERSION_STRING);
     }
     catch (...)
     {
+        /// It is OK not to terminate under an error from ZSTD_freeCCtx()
+        /// since all data already written to the stream.
         tryLogCurrentException(__PRETTY_FUNCTION__);
     }
 }
diff --git a/src/Server/TCPHandler.cpp b/src/Server/TCPHandler.cpp
index d66639ef111..c207d188a85 100644
--- a/src/Server/TCPHandler.cpp
+++ b/src/Server/TCPHandler.cpp
@@ -1,6 +1,7 @@
 #include <iomanip>
 #include <ext/scope_guard.h>
 #include <Poco/Net/NetException.h>
+#include <Poco/Util/LayeredConfiguration.h>
 #include <Common/CurrentThread.h>
 #include <Common/Stopwatch.h>
 #include <Common/NetException.h>
@@ -56,6 +57,28 @@ namespace ErrorCodes
     extern const int SUPPORT_IS_DISABLED;
 }
 
+TCPHandler::TCPHandler(IServer & server_, const Poco::Net::StreamSocket & socket_, bool parse_proxy_protocol_, std::string server_display_name_)
+    : Poco::Net::TCPServerConnection(socket_)
+    , server(server_)
+    , parse_proxy_protocol(parse_proxy_protocol_)
+    , log(&Poco::Logger::get("TCPHandler"))
+    , connection_context(server.context())
+    , query_context(server.context())
+    , server_display_name(std::move(server_display_name_))
+{
+}
+TCPHandler::~TCPHandler()
+{
+    try
+    {
+        state.reset();
+        out->next();
+    }
+    catch (...)
+    {
+        tryLogCurrentException(__PRETTY_FUNCTION__);
+    }
+}
 
 void TCPHandler::runImpl()
 {
diff --git a/src/Server/TCPHandler.h b/src/Server/TCPHandler.h
index 41539bef1e1..ee2f7c96b5a 100644
--- a/src/Server/TCPHandler.h
+++ b/src/Server/TCPHandler.h
@@ -10,6 +10,7 @@
 #include <IO/Progress.h>
 #include <DataStreams/BlockIO.h>
 #include <Interpreters/InternalTextLogsQueue.h>
+#include <Interpreters/Context.h>
 #include <Client/TimeoutSetter.h>
 
 #include "IServer.h"
@@ -113,16 +114,8 @@ public:
       * Proxy-forwarded (original client) IP address is used for quota accounting if quota is keyed by forwarded IP.
       */
     TCPHandler(IServer & server_, const Poco::Net::StreamSocket & socket_, bool parse_proxy_protocol_,
-        std::string server_display_name_)
-        : Poco::Net::TCPServerConnection(socket_)
-        , server(server_)
-        , parse_proxy_protocol(parse_proxy_protocol_)
-        , log(&Poco::Logger::get("TCPHandler"))
-        , connection_context(server.context())
-        , query_context(server.context())
-        , server_display_name(std::move(server_display_name_))
-    {
-    }
+        std::string server_display_name_);
+    ~TCPHandler() override;
 
     void run() override;