diff --git a/exec_helpers/__init__.py b/exec_helpers/__init__.py
index 06f3003..b4a4012 100644
--- a/exec_helpers/__init__.py
+++ b/exec_helpers/__init__.py
@@ -51,7 +51,7 @@
     "ExecResult",
 )
 
-__version__ = "1.4.0"
+__version__ = "1.4.1"
 __author__ = "Alexey Stepanov"
 __author_email__ = "penguinolog@gmail.com"
 __maintainers__ = {
diff --git a/exec_helpers/_ssh_client_base.py b/exec_helpers/_ssh_client_base.py
index 5eeacfe..b8111dc 100644
--- a/exec_helpers/_ssh_client_base.py
+++ b/exec_helpers/_ssh_client_base.py
@@ -22,7 +22,7 @@
 
 import abc
 import base64
-import collections
+
 # noinspection PyCompatibility
 import concurrent.futures
 import copy
@@ -98,19 +98,6 @@ class _MemorizedSSH(abc.ABCMeta):
 
     __cache = {}  # type: typing.Dict[typing.Tuple[str, int], SSHClientBase]
 
-    @classmethod
-    def __prepare__(
-        mcs,  # type: typing.Type[_MemorizedSSH]
-        name,  # type: str
-        bases,  # type: typing.Iterable[typing.Type]
-        **kwargs  # type: typing.Any
-    ):  # type: (...) -> collections.OrderedDict  # pylint: disable=unused-argument
-        """Metaclass magic for object storage.
-
-        .. versionadded:: 1.2.0
-        """
-        return collections.OrderedDict()  # pragma: no cover
-
     def __call__(  # type: ignore
         cls,  # type: _MemorizedSSH
         host,  # type: str
@@ -650,7 +637,7 @@ def poll_streams():  # type: () -> None
             if stderr and interface.recv_stderr_ready():
                 result.read_stderr(src=stderr, log=self.logger, verbose=verbose)
 
-        @threaded.threadpooled  # type: ignore
+        @threaded.threadpooled
         def poll_pipes(stop,):  # type: (threading.Event) -> None
             """Polling task for FIFO buffers.
 
@@ -807,7 +794,7 @@ def execute_together(
         .. versionchanged:: 1.2.0 default timeout 1 hour
         .. versionchanged:: 1.2.0 log_mask_re regex rule for masking cmd
         """
-        @threaded.threadpooled  # type: ignore
+        @threaded.threadpooled
         def get_result(remote):  # type: (SSHClientBase) -> exec_result.ExecResult
             """Get result from remote call."""
             async_result = remote.execute_async(command, **kwargs)  # type: SshExecuteAsyncResult
diff --git a/exec_helpers/proc_enums.py b/exec_helpers/proc_enums.py
index 4d4656d..7be3b36 100644
--- a/exec_helpers/proc_enums.py
+++ b/exec_helpers/proc_enums.py
@@ -155,7 +155,7 @@ def exit_code_to_enum(code):  # type: (typing.Union[int, ExitCodes]) -> typing.U
     """Convert exit code to enum if possible."""
     if isinstance(code, int) and code in ExitCodes.__members__.values():
         return ExitCodes(code)
-    return code
+    return code  # pragma: no cover
 
 
 def exit_codes_to_enums(
diff --git a/exec_helpers/ssh_auth.py b/exec_helpers/ssh_auth.py
index 8507017..67ba5d4 100644
--- a/exec_helpers/ssh_auth.py
+++ b/exec_helpers/ssh_auth.py
@@ -209,15 +209,13 @@ def __ne__(self, other):  # type: (typing.Any) -> bool
 
     def __deepcopy__(self, memo):  # type: (typing.Any) -> SSHAuth
         """Helper for copy.deepcopy."""
-        return self.__class__(  # type: ignore
+        return self.__class__(
             username=self.username, password=self.__password, key=self.__key, keys=copy.deepcopy(self.__keys)
         )
 
     def __copy__(self):  # type: () -> SSHAuth
         """Copy self."""
-        return self.__class__(  # type: ignore
-            username=self.username, password=self.__password, key=self.__key, keys=self.__keys
-        )
+        return self.__class__(username=self.username, password=self.__password, key=self.__key, keys=self.__keys)
 
     def __repr__(self):  # type: (...) -> str
         """Representation for debug purposes."""
diff --git a/exec_helpers/subprocess_runner.py b/exec_helpers/subprocess_runner.py
index 3598b9d..df1d77d 100644
--- a/exec_helpers/subprocess_runner.py
+++ b/exec_helpers/subprocess_runner.py
@@ -21,17 +21,19 @@
 from __future__ import unicode_literals
 
 import abc
-import collections
+
 # noinspection PyCompatibility
 import concurrent.futures
 import errno
 import logging
 import os
+import platform
 import subprocess  # nosec  # Expected usage
 import threading
 import typing  # noqa: F401  # pylint: disable=unused-import
 
 import six
+import psutil  # type: ignore
 import threaded
 
 from exec_helpers import api
@@ -44,6 +46,39 @@
 devnull = open(os.devnull)  # subprocess.DEVNULL is py3.3+
 
 
+# Adopt from:
+# https://stackoverflow.com/questions/1230669/subprocess-deleting-child-processes-in-windows
+def kill_proc_tree(pid, including_parent=True):  # type: (int, bool) -> None  # pragma: no cover
+    """Kill process tree.
+
+    :param pid: PID of parent process to kill
+    :type pid: int
+    :param including_parent: kill also parent process
+    :type including_parent: bool
+    """
+    parent = psutil.Process(pid)
+    children = parent.children(recursive=True)
+    for child in children:  # type: psutil.Process
+        child.kill()
+    _, alive = psutil.wait_procs(children, timeout=5)
+    for proc in alive:  # type: psutil.Process
+        proc.kill()  # 2nd shot
+    if including_parent:
+        parent.kill()
+        parent.wait(5)
+
+
+# Subprocess extra arguments.
+# Flags from:
+# https://stackoverflow.com/questions/13243807/popen-waiting-for-child-process-even-when-the-immediate-child-has-terminated
+kw = {}  # type: typing.Dict[str, typing.Any]
+if "Windows" == platform.system():  # pragma: no cover
+    kw["creationflags"] = 0x00000200
+else:  # pragma: no cover
+    kw["preexec_fn"] = os.setsid
+
+
+# noinspection PyTypeHints
 class SubprocessExecuteAsyncResult(api.ExecuteAsyncResult):
     """Override original NamedTuple with proper typing."""
 
@@ -70,19 +105,6 @@ def __call__(cls, *args, **kwargs):  # type: (SingletonMeta, typing.Any, typing.
                 cls._instances[cls] = super(SingletonMeta, cls).__call__(*args, **kwargs)
         return cls._instances[cls]
 
-    @classmethod
-    def __prepare__(
-        mcs,
-        name,  # type: str
-        bases,  # type: typing.Iterable[typing.Type]
-        **kwargs  # type: typing.Any
-    ):  # type: (...) -> collections.OrderedDict  # pylint: disable=unused-argument
-        """Metaclass magic for object storage.
-
-        .. versionadded:: 1.2.0
-        """
-        return collections.OrderedDict()  # pragma: no cover
-
 
 class Subprocess(six.with_metaclass(SingletonMeta, api.ExecHelper)):
     """Subprocess helper with timeouts and lock-free FIFO."""
@@ -138,17 +160,24 @@ def _exec_command(
 
         .. versionadded:: 1.2.0
         """
-        @threaded.threadpooled  # type: ignore
+        @threaded.threadpooled
         def poll_stdout():  # type: () -> None
             """Sync stdout poll."""
             result.read_stdout(src=stdout, log=logger, verbose=verbose)
             interface.wait()  # wait for the end of execution
 
-        @threaded.threadpooled  # type: ignore
+        @threaded.threadpooled
         def poll_stderr():  # type: () -> None
             """Sync stderr poll."""
             result.read_stderr(src=stderr, log=logger, verbose=verbose)
 
+        def close_streams():  # type: () -> None
+            """Enforce FIFO closure."""
+            if stdout is not None and not stdout.closed:
+                stdout.close()
+            if stderr is not None and not stderr.closed:
+                stderr.close()
+
         # Store command with hidden data
         cmd_for_log = self._mask_command(cmd=command, log_mask_re=log_mask_re)
 
@@ -167,11 +196,13 @@ def poll_stderr():  # type: () -> None
         # Process closed?
         if exit_code is not None:
             result.exit_code = exit_code
+            close_streams()
             return result
         # Kill not ended process and wait for close
         try:
+            kill_proc_tree(interface.pid, including_parent=False)  # kill -9 for all subprocesses
             interface.kill()  # kill -9
-            concurrent.futures.wait([stdout_future, stderr_future], timeout=5)
+            concurrent.futures.wait([stdout_future, stderr_future], timeout=0.5)
             # Force stop cycle if no exit code after kill
             stdout_future.cancel()
             stderr_future.cancel()
@@ -182,6 +213,8 @@ def poll_stderr():  # type: () -> None
                 result.exit_code = exit_code
                 return result
             raise  # Some other error
+        finally:
+            close_streams()
 
         wait_err_msg = _log_templates.CMD_WAIT_ERROR.format(result=result, timeout=timeout)
         logger.debug(wait_err_msg)
@@ -244,6 +277,7 @@ def execute_async(
             cwd=kwargs.get("cwd", None),
             env=kwargs.get("env", None),
             universal_newlines=False,
+            **kw
         )
 
         if stdin is None:
@@ -264,6 +298,7 @@ def execute_async(
                 elif exc.errno in (errno.EPIPE, errno.ESHUTDOWN):  # pragma: no cover
                     self.logger.warning("STDIN Send failed: broken PIPE")
                 else:
+                    kill_proc_tree(process.pid)
                     process.kill()
                     raise
             try:
diff --git a/requirements.txt b/requirements.txt
index 746aefe..3f2b2bd 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -7,3 +7,4 @@ advanced-descriptors>=1.0  # Apache-2.0
 typing >= 3.6  # PSF
 futures>=3.1; python_version == "2.7"
 enum34>=1.1; python_version == "2.7"
+psutil >= 5.0
diff --git a/test/test_subprocess_runner.py b/test/test_subprocess_runner.py
index 144c58d..f3a3c44 100644
--- a/test/test_subprocess_runner.py
+++ b/test/test_subprocess_runner.py
@@ -22,6 +22,8 @@
 
 import errno
 import logging
+import os
+import platform
 import subprocess
 import unittest
 
@@ -40,6 +42,7 @@
 class FakeFileStream(object):
     def __init__(self, *args):
         self.__src = list(args)
+        self.closed = False
 
     def __iter__(self):
         for _ in range(len(self.__src)):
@@ -48,9 +51,23 @@ def __iter__(self):
     def fileno(self):
         return hash(tuple(self.__src))
 
+    def close(self):
+        self.closed = True
 
-@mock.patch('exec_helpers.subprocess_runner.logger', autospec=True)
-@mock.patch('subprocess.Popen', autospec=True, name='subprocess.Popen')
+
+# Subprocess extra arguments.
+# Flags from:
+# https://stackoverflow.com/questions/13243807/popen-waiting-for-child-process-even-when-the-immediate-child-has-terminated
+kw = {}
+if 'Windows' == platform.system():
+    kw['creationflags'] = 0x00000200
+else:
+    kw["preexec_fn"] = os.setsid
+
+
+@mock.patch("psutil.Process", autospec=True)
+@mock.patch("exec_helpers.subprocess_runner.logger", autospec=True)
+@mock.patch("subprocess.Popen", autospec=True, name="subprocess.Popen")
 class TestSubprocessRunner(unittest.TestCase):
     def setUp(self):
         subprocess_runner.SingletonMeta._instances.clear()
@@ -108,7 +125,8 @@ def gen_cmd_result_log_message(result):
     def test_001_call(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):  # type: (...) -> None
         popen_obj, exp_result = self.prepare_close(popen)
 
@@ -127,6 +145,7 @@ def test_001_call(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
@@ -145,7 +164,8 @@ def test_001_call(
     def test_002_call_verbose(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):  # type: (...) -> None
         popen_obj, _ = self.prepare_close(popen)
 
@@ -166,7 +186,7 @@ def test_002_call_verbose(
     def test_003_context_manager(
         self,
         popen,  # type: mock.MagicMock
-        _  # type: mock.MagicMock
+        *args  # type: mock.MagicMock
     ):  # type: (...) -> None
         popen_obj, exp_result = self.prepare_close(popen)
 
@@ -193,7 +213,7 @@ def test_004_execute_timeout_fail(
         self,
         _,  # type: mock.MagicMock
         popen,  # type: mock.MagicMock
-        __  # type: mock.MagicMock
+        *args  # type: mock.MagicMock
     ):
         popen_obj, exp_result = self.prepare_close(popen)
         popen_obj.poll.return_value = None
@@ -222,13 +242,15 @@ def test_004_execute_timeout_fail(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
     def test_005_execute_no_stdout(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):
         popen_obj, exp_result = self.prepare_close(popen, open_stdout=False)
 
@@ -247,6 +269,7 @@ def test_005_execute_no_stdout(
                 stdin=subprocess.PIPE,
                 stdout=subprocess_runner.devnull,
                 universal_newlines=False,
+                **kw
             ),
         ))
         logger.assert_has_calls(
@@ -269,7 +292,8 @@ def test_005_execute_no_stdout(
     def test_006_execute_no_stderr(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):
         popen_obj, exp_result = self.prepare_close(popen, open_stderr=False)
 
@@ -288,6 +312,7 @@ def test_006_execute_no_stderr(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
         logger.assert_has_calls(
@@ -311,7 +336,8 @@ def test_006_execute_no_stderr(
     def test_007_execute_no_stdout_stderr(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):
         popen_obj, exp_result = self.prepare_close(
             popen,
@@ -334,6 +360,7 @@ def test_007_execute_no_stdout_stderr(
                 stdin=subprocess.PIPE,
                 stdout=subprocess_runner.devnull,
                 universal_newlines=False,
+                **kw
             ),
         ))
         logger.assert_has_calls(
@@ -351,7 +378,8 @@ def test_007_execute_no_stdout_stderr(
     def test_008_execute_mask_global(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):
         cmd = "USE='secret=secret_pass' do task"
         log_mask_re = r"secret\s*=\s*([A-Z-a-z0-9_\-]+)"
@@ -381,6 +409,7 @@ def test_008_execute_mask_global(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
@@ -400,7 +429,8 @@ def test_008_execute_mask_global(
     def test_009_execute_mask_local(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):
         cmd = "USE='secret=secret_pass' do task"
         log_mask_re = r"secret\s*=\s*([A-Z-a-z0-9_\-]+)"
@@ -428,6 +458,7 @@ def test_009_execute_mask_local(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
         self.assertEqual(
@@ -445,7 +476,7 @@ def test_009_execute_mask_local(
     def test_004_check_stdin_str(
         self,
         popen,  # type: mock.MagicMock
-        _  # type: mock.MagicMock
+        *args  # type: mock.MagicMock
     ):  # type: (...) -> None
         stdin = u'this is a line'
 
@@ -470,6 +501,7 @@ def test_004_check_stdin_str(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
@@ -481,7 +513,7 @@ def test_004_check_stdin_str(
     def test_005_check_stdin_bytes(
         self,
         popen,  # type: mock.MagicMock
-        _  # type: mock.MagicMock
+        *args  # type: mock.MagicMock
     ):  # type: (...) -> None
         stdin = b'this is a line'
 
@@ -506,6 +538,7 @@ def test_005_check_stdin_bytes(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
@@ -517,7 +550,7 @@ def test_005_check_stdin_bytes(
     def test_006_check_stdin_bytearray(
         self,
         popen,  # type: mock.MagicMock
-        _  # type: mock.MagicMock
+        *args  # type: mock.MagicMock
     ):  # type: (...) -> None
         stdin = bytearray(b'this is a line')
 
@@ -542,6 +575,7 @@ def test_006_check_stdin_bytearray(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
@@ -553,7 +587,8 @@ def test_006_check_stdin_bytearray(
     def test_008_check_stdin_fail_closed_win(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):  # type: (...) -> None
         stdin = b'this is a line'
 
@@ -581,6 +616,7 @@ def test_008_check_stdin_fail_closed_win(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
@@ -593,7 +629,7 @@ def test_008_check_stdin_fail_closed_win(
     def test_009_check_stdin_fail_write(
         self,
         popen,  # type: mock.MagicMock
-        _  # type: mock.MagicMock
+        *args  # type: mock.MagicMock
     ):  # type: (...) -> None
         stdin = b'this is a line'
 
@@ -615,7 +651,8 @@ def test_009_check_stdin_fail_write(
     def test_011_check_stdin_fail_close_pipe_win(
         self,
         popen,  # type: mock.MagicMock
-        logger  # type: mock.MagicMock
+        logger,  # type: mock.MagicMock
+        *args
     ):  # type: (...) -> None
         stdin = b'this is a line'
 
@@ -643,6 +680,7 @@ def test_011_check_stdin_fail_close_pipe_win(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
@@ -655,7 +693,7 @@ def test_011_check_stdin_fail_close_pipe_win(
     def test_012_check_stdin_fail_close(
         self,
         popen,  # type: mock.MagicMock
-        _  # type: mock.MagicMock
+        *args  # type: mock.MagicMock
     ):  # type: (...) -> None
         stdin = b'this is a line'
 
@@ -679,7 +717,7 @@ def test_013_execute_timeout_done(
         self,
         _,  # type: mock.MagicMock
         popen,  # type: mock.MagicMock
-        __  # type: mock.MagicMock
+        *args  # type: mock.MagicMock
 
     ):
         popen_obj, exp_result = self.prepare_close(popen, ec=exec_helpers.ExitCodes.EX_INVALID)
@@ -704,6 +742,7 @@ def test_013_execute_timeout_done(
                 stdin=subprocess.PIPE,
                 stdout=subprocess.PIPE,
                 universal_newlines=False,
+                **kw
             ),
         ))
 
@@ -711,7 +750,7 @@ def test_013_execute_timeout_done(
 @mock.patch('exec_helpers.subprocess_runner.logger', autospec=True)
 @mock.patch('exec_helpers.subprocess_runner.Subprocess.execute')
 class TestSubprocessRunnerHelpers(unittest.TestCase):
-    def test_001_check_call(self, execute, logger):
+    def test_001_check_call(self, execute, *args):
         exit_code = 0
         return_value = exec_helpers.ExecResult(
             cmd=command,
@@ -745,7 +784,7 @@ def test_001_check_call(self, execute, logger):
             runner.check_call(command=command, verbose=verbose, timeout=None)
         execute.assert_called_once_with(command, verbose, None)
 
-    def test_002_check_call_expected(self, execute, logger):
+    def test_002_check_call_expected(self, execute, *args):
         exit_code = 0
         return_value = exec_helpers.ExecResult(
             cmd=command,