Socket报错：BlockingIOError和greenlet.error

报错：

  BlockingIOError: [Errno 11] Resource temporarily unavailable
  greenlet.error: cannot switch to a different thread

Exception in thread Thread-1:
Traceback (most recent call last):
  File "/root/miniconda3/envs/fancp/lib/python3.6/site-packages/gevent/_socketcommon.py", line 722, in send
    return self._sock.send(data, flags)
BlockingIOError: [Errno 11] Resource temporarily unavailable

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/root/miniconda3/envs/fancp/lib/python3.6/threading.py", line 916, in _bootstrap_inner
    self.run()
  File "/root/miniconda3/envs/fancp/lib/python3.6/threading.py", line 864, in run
    self._target(*self._args, **self._kwargs)
  File "server2.py", line 43, in run
    ws.send(js_data)
  File "/root/miniconda3/envs/fancp/lib/python3.6/site-packages/geventwebsocket/websocket.py", line 344, in send
    self.send_frame(message, opcode)
  File "/root/miniconda3/envs/fancp/lib/python3.6/site-packages/geventwebsocket/websocket.py", line 328, in send_frame
    self.raw_write(header + message)
  File "/root/miniconda3/envs/fancp/lib/python3.6/site-packages/gevent/_socketcommon.py", line 699, in sendall
    return _sendall(self, data_memory, flags)
  File "/root/miniconda3/envs/fancp/lib/python3.6/site-packages/gevent/_socketcommon.py", line 409, in _sendall
    timeleft = __send_chunk(socket, chunk, flags, timeleft, end)
  File "/root/miniconda3/envs/fancp/lib/python3.6/site-packages/gevent/_socketcommon.py", line 338, in __send_chunk
    data_sent += socket.send(chunk, flags)
  File "/root/miniconda3/envs/fancp/lib/python3.6/site-packages/gevent/_socketcommon.py", line 727, in send
    self._wait(self._write_event)
  File "src/gevent/_hub_primitives.py", line 317, in gevent._gevent_c_hub_primitives.wait_on_socket
  File "src/gevent/_hub_primitives.py", line 322, in gevent._gevent_c_hub_primitives.wait_on_socket
  File "src/gevent/_hub_primitives.py", line 304, in gevent._gevent_c_hub_primitives._primitive_wait
  File "src/gevent/_hub_primitives.py", line 46, in gevent._gevent_c_hub_primitives.WaitOperationsGreenlet.wait
  File "src/gevent/_hub_primitives.py", line 46, in gevent._gevent_c_hub_primitives.WaitOperationsGreenlet.wait
  File "src/gevent/_hub_primitives.py", line 55, in gevent._gevent_c_hub_primitives.WaitOperationsGreenlet.wait
  File "src/gevent/_waiter.py", line 154, in gevent._gevent_c_waiter.Waiter.get
  File "src/gevent/_greenlet_primitives.py", line 61, in gevent._gevent_c_greenlet_primitives.SwitchOutGreenletWithLoop.switch
  File "src/gevent/_greenlet_primitives.py", line 61, in gevent._gevent_c_greenlet_primitives.SwitchOutGreenletWithLoop.switch
  File "src/gevent/_greenlet_primitives.py", line 65, in gevent._gevent_c_greenlet_primitives.SwitchOutGreenletWithLoop.switch
  File "src/gevent/_gevent_c_greenlet_primitives.pxd", line 35, in gevent._gevent_c_greenlet_primitives._greenlet_switch
greenlet.error: cannot switch to a different thread

解决方法：
  可参考：https://blog.csdn.net/pythontide/article/details/109242386

try:
    sock.send('hello world!'.encode())
except BlockingIOError as err:
    time.sleep(1)
    sock.send('hello world!'.encode())

实际方法：
  导致问题的原因是socket的ws.send(js_data)发送数据太频繁。
  加入延时即可time.sleep(0.05)。