@@ -81,7 +81,11 @@ class MultiPartUpload(object):

         chunk_size = max(self.MIN_CHUNK_SIZE, chunk_size)

         id = 1

-        pool = ThreadPool(num_threads)

+        if num_threads > 1:

+            debug("MultiPart: Uploading in %d threads" % num_threads)

+            pool = ThreadPool(num_threads)

+        else:

+            debug("MultiPart: Uploading in a single thread")

         while True:

             if id == self.MAX_CHUNKS:

@@ -90,11 +94,15 @@ class MultiPartUpload(object):

                 data = self.file.read(chunk_size)

             if not data:

                 break

-            pool.add_task(self.upload_part, data, id)

+            if num_threads > 1:

+                pool.add_task(self.upload_part, data, id)

+            else:

+                self.upload_part(data, id)

             id += 1

-        debug("Thread pool with %i threads and %i tasks awaiting completion." % (num_threads, id))

-        pool.wait_completion()

+        if num_threads > 1:

+            debug("Thread pool with %i threads and %i tasks awaiting completion." % (num_threads, id))

+            pool.wait_completion()

     def upload_part(self, data, id):

         """