UI improvement for asyncio (#6905)

python/ray/async_compat.py

@@ -3,8 +3,9 @@ This file should only be imported from Python 3.
 It will raise SyntaxError when importing from Python 2.
 """
 import asyncio
-from collections import namedtuple
+from collections import namedtuple, Counter
 import time
+import threading
 
 import ray
 
@@ -96,3 +97,35 @@ def get_async(object_id):
     user_future.object_id = object_id
 
     return user_future
+
+
+class AsyncMonitorState:
+    def __init__(self, loop):
+        self.names = dict()
+        self.names_lock = threading.Lock()
+
+        self.sleep_time = 1.0
+        asyncio.ensure_future(self.monitor(), loop=loop)
+
+    async def monitor(self):
+        while True:
+            await asyncio.sleep(self.sleep_time)
+            all_tasks = self.get_all_task_names()
+            ray.show_in_webui(
+                str(len(all_tasks)), key="Number of concurrent task runing")
+            ray.show_in_webui(
+                str(dict(Counter(all_tasks))), key="Concurrent tasks")
+
+    def register_coroutine(self, coro, name):
+        with self.names_lock:
+            self.names[coro] = name
+
+    def unregister_coroutine(self, coro):
+        with self.names_lock:
+            self.names.pop(coro)
+
+    def get_all_task_names(self):
+        names = []
+        with self.names_lock:
+            names = list(self.names.values())
+        return names