Add option for max number of streams

src/AsapoWorker/streamer_manager.py

@@ -9,9 +9,13 @@ log = logging.getLogger(__name__)
 
 
 class StreamerManager:
-    def __init__(self, create_streamer):
+    def __init__(self, create_streamer, max_streams=16):
         self._create_streamer = create_streamer
-        self.executor = ThreadPoolExecutor(max_workers=16)
+        self.max_streams = max_streams
+        # Temporarily, there can be more than max_streams threads,
+        # therefore the thread pool should be a bit larger
+        # (number of additional threads chosen by fair dice roll)
+        self.executor = ThreadPoolExecutor(max_workers=max_streams + 4)
         self.streamers = OrderedDict()
         self.futures = OrderedDict()
         self.stopped = Event()
@@ -46,7 +50,7 @@ class StreamerManager:
                 self.streamers[substream] = streamer
                 self.futures[substream] = future
 
-    def stop_old_streamers(self, n_max=10):
+    def stop_old_streamers(self, n_max):
         with self.lock:
             for streamer in not_last_n(n_max, self.streamers.values()):
                 log.info("Stopping substream=%s", streamer.receiver.substream)
@@ -96,7 +100,7 @@ class StreamerManager:
                 self.stop_old_streamers(n_max=0)
                 time.sleep(0.5)  # replace wait which now returns immediately
             else:
-                self.stop_old_streamers()
+                self.stop_old_streamers(n_max=self.max_streams)
 
             self.cleanup_stopped_streamers()