diff --git a/pypeln/process/api/map_process_test.py b/pypeln/process/api/map_process_test.py
index 56f2daa..5930044 100644
--- a/pypeln/process/api/map_process_test.py
+++ b/pypeln/process/api/map_process_test.py
@@ -189,3 +189,27 @@ def raise_error(x):
         error = e
 
     assert isinstance(error, MyError)
+
+
+def test_maxsize():
+
+    namespace = pl.process.utils.Namespace(count=0)
+
+    def f(x) -> tp.Any:
+        namespace.count += 1
+        return x
+
+    stage = pl.process.map(f, range(20))
+    stage = pl.process.to_iterable(stage, maxsize=3)
+
+    iterator = iter(stage)
+    next(iterator)
+
+    time.sleep(0.1)
+
+    # + 1 element which was yieled on next(...)
+    # + 3 elements which are on the queue.
+    # + 1 element which it pending to be put.
+    # -------------------------------------------
+    # + 5 total
+    assert namespace.count == 5
diff --git a/pypeln/process/stage.py b/pypeln/process/stage.py
index ac10f65..23c02fe 100644
--- a/pypeln/process/stage.py
+++ b/pypeln/process/stage.py
@@ -88,4 +88,4 @@ def to_iterable(self, maxsize: int, return_index: bool) -> tp.Iterable[T]:
                     yield elem.value
 
     def __iter__(self):
-        return self.to_iterable(maxsize=0, return_index=False)
+        return self.to_iterable(maxsize=self.maxsize, return_index=False)
diff --git a/pypeln/task/api/map_task_test.py b/pypeln/task/api/map_task_test.py
index c611846..928f732 100644
--- a/pypeln/task/api/map_task_test.py
+++ b/pypeln/task/api/map_task_test.py
@@ -418,3 +418,27 @@ def raise_error(x):
         error = e
 
     assert isinstance(error, MyError)
+
+
+def test_maxsize():
+
+    namespace = pl.task.utils.Namespace(count=0)
+
+    def f(x) -> tp.Any:
+        namespace.count += 1
+        return x
+
+    stage = pl.task.map(f, range(20))
+    stage = pl.task.to_iterable(stage, maxsize=3)
+
+    iterator = iter(stage)
+    next(iterator)
+
+    time.sleep(0.1)
+
+    # + 1 element which was yieled on next(...)
+    # + 3 elements which are on the queue.
+    # + 1 element which it pending to be put.
+    # -------------------------------------------
+    # + 5 total
+    assert namespace.count == 5
diff --git a/pypeln/task/stage.py b/pypeln/task/stage.py
index 3ad3852..2194b0f 100644
--- a/pypeln/task/stage.py
+++ b/pypeln/task/stage.py
@@ -105,10 +105,10 @@ async def to_async_iterable(
                     yield elem.value
 
     def __iter__(self):
-        return self.to_iterable(maxsize=0, return_index=False)
+        return self.to_iterable(maxsize=self.maxsize, return_index=False)
 
     def __aiter__(self):
-        return self.to_async_iterable(maxsize=0, return_index=False)
+        return self.to_async_iterable(maxsize=self.maxsize, return_index=False)
 
     async def _await(self):
         return [x async for x in self]
diff --git a/pypeln/task/supervisor.py b/pypeln/task/supervisor.py
index 0cd9303..c1ff1ad 100644
--- a/pypeln/task/supervisor.py
+++ b/pypeln/task/supervisor.py
@@ -32,6 +32,8 @@ def stop_nowait(self):
             worker.stop()
 
         while any(not worker.is_done for worker in self.workers):
+            # for worker in self.workers:
+            #     worker.stop()
             time.sleep(pypeln_utils.TIMEOUT)
 
     def start(self):
diff --git a/pypeln/task/utils.py b/pypeln/task/utils.py
index b20efda..bcf9c70 100644
--- a/pypeln/task/utils.py
+++ b/pypeln/task/utils.py
@@ -22,7 +22,8 @@ def get_running_loop() -> asyncio.AbstractEventLoop:
     if not loop.is_running():
 
         def run():
-            loop.run_forever()
+            if not loop.is_running():
+                loop.run_forever()
 
         thread = threading.Thread(target=run)
         thread.daemon = True
diff --git a/pypeln/task/worker.py b/pypeln/task/worker.py
index 4fcdcdc..834e9f9 100644
--- a/pypeln/task/worker.py
+++ b/pypeln/task/worker.py
@@ -127,9 +127,9 @@ async def __call__(self):
         except BaseException as e:
             await self.main_queue.raise_exception(e)
         finally:
+            self.is_done = True
             self.tasks.stop()
             await self.stage_params.output_queues.done()
-            self.is_done = True
 
     def start(self):
         [self.process] = start_workers(self)
@@ -139,8 +139,12 @@ def stop(self):
         if self.process is None:
             return
 
+        def cancel():
+            self.process.cancel()
+            # self.is_done = True
+
         self.tasks.stop()
-        utils.run_function_in_loop(self.process.cancel)
+        utils.run_function_in_loop(cancel)
 
 
 class Applicable(pypeln_utils.Protocol):
diff --git a/pypeln/thread/api/map_thread_test.py b/pypeln/thread/api/map_thread_test.py
index 6d50a9a..4a16fc7 100644
--- a/pypeln/thread/api/map_thread_test.py
+++ b/pypeln/thread/api/map_thread_test.py
@@ -189,3 +189,27 @@ def raise_error(x):
         error = e
 
     assert isinstance(error, MyError)
+
+
+def test_maxsize():
+
+    namespace = pl.thread.utils.Namespace(count=0)
+
+    def f(x) -> tp.Any:
+        namespace.count += 1
+        return x
+
+    stage = pl.thread.map(f, range(20))
+    stage = pl.thread.to_iterable(stage, maxsize=3)
+
+    iterator = iter(stage)
+    next(iterator)
+
+    time.sleep(0.1)
+
+    # + 1 element which was yieled on next(...)
+    # + 3 elements which are on the queue.
+    # + 1 element which it pending to be put.
+    # -------------------------------------------
+    # + 5 total
+    assert namespace.count == 5
diff --git a/pypeln/thread/queue.py b/pypeln/thread/queue.py
index 870ef5a..150da73 100644
--- a/pypeln/thread/queue.py
+++ b/pypeln/thread/queue.py
@@ -1,15 +1,13 @@
-import multiprocessing
-from multiprocessing.queues import Empty, Queue
 import sys
+import time
 import traceback
 import typing as tp
-
+from queue import Queue, Empty, Full
+from threading import Lock
 
 from pypeln import utils as pypeln_utils
 
 from . import utils
-import time
-
 
 T = tp.TypeVar("T")
 
@@ -21,19 +19,25 @@ class PipelineException(tp.NamedTuple, BaseException):
 
 class IterableQueue(Queue, tp.Generic[T], tp.Iterable[T]):
     def __init__(self, maxsize: int = 0, total_sources: int = 1):
-        super().__init__(maxsize=maxsize, ctx=multiprocessing.get_context())
+        super().__init__(maxsize=maxsize)
 
-        self.lock = multiprocessing.Lock()
+        self.lock = Lock()
         self.namespace = utils.Namespace(
             remaining=total_sources, exception=False, force_stop=False
         )
-        self.exception_queue: Queue[PipelineException] = Queue(
-            ctx=multiprocessing.get_context()
-        )
+        self.exception_queue: "Queue[PipelineException]" = Queue()
 
     def get(self, *arg, **kwargs) -> T:
         return super().get(*arg, **kwargs)
 
+    def put(self, x: T):
+        while True:
+            try:
+                super().put(x, timeout=pypeln_utils.TIMEOUT)
+                return
+            except Full as e:
+                pass
+
     def __iter__(self) -> tp.Iterator[T]:
 
         while not self.is_done():
diff --git a/pypeln/thread/stage.py b/pypeln/thread/stage.py
index 13fbbcd..382bbf0 100644
--- a/pypeln/thread/stage.py
+++ b/pypeln/thread/stage.py
@@ -86,4 +86,4 @@ def to_iterable(self, maxsize: int, return_index: bool) -> tp.Iterable[T]:
                     yield elem.value
 
     def __iter__(self):
-        return self.to_iterable(maxsize=0, return_index=False)
+        return self.to_iterable(maxsize=self.maxsize, return_index=False)
diff --git a/pypeln/thread/supervisor.py b/pypeln/thread/supervisor.py
index b483d43..4da3ee5 100644
--- a/pypeln/thread/supervisor.py
+++ b/pypeln/thread/supervisor.py
@@ -46,8 +46,14 @@ def __exit__(self, *args):
             worker.stop()
 
         while any(worker.process.is_alive() for worker in self.workers):
+            print([worker.process.is_alive() for worker in self.workers])
+            for worker in self.workers:
+                worker.stop()
+
             time.sleep(pypeln_utils.TIMEOUT)
 
+        print("EXIT")
+
     def start(self):
 
         for worker in self.workers: