I was experiencing the same as https://github.com/holoviz/panel/issues/1405 and I found that it only happened when I from holoviews.operation.datashader import datashade
. Here’s a minimal example:
#!/usr/bin/env python3.8
import panel
import holoviews
# This line breaks things:
from holoviews.operation.datashader import datashade
print(panel.__version__)
print(holoviews.__version__)
panel.serve(
panel.pane.Markdown("#1"),
port=8008,
show=True,
num_procs=2
)
0.10.0
1.13.5
Launching server at http://localhost:8008
Traceback (most recent call last):
File "/usr/lib/python3.8/asyncio/selector_events.py", line 259, in _add_reader
key = self._selector.get_key(fd)
File "/usr/lib/python3.8/selectors.py", line 192, in get_key
raise KeyError("{!r} is not registered".format(fileobj)) from None
KeyError: '6 is not registered'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "../.config/JetBrains/PyCharmCE2020.2/scratches/scratch_1.py", line 12, in <module>
panel.serve(
File "/home/rick/panel/panel/io/server.py", line 208, in serve
server = get_server(panels, **kwargs)
File "/home/rick/panel/panel/io/server.py", line 380, in get_server
server = Server(apps, port=port, **opts)
File "/home/rick/.local/lib/python3.8/site-packages/bokeh/server/server.py", line 415, in __init__
http_server.add_sockets(sockets)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/tcpserver.py", line 165, in add_sockets
self._handlers[sock.fileno()] = add_accept_handler(
File "/home/rick/.local/lib/python3.8/site-packages/tornado/netutil.py", line 279, in add_accept_handler
io_loop.add_handler(sock, accept_handler, IOLoop.READ)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/platform/asyncio.py", line 100, in add_handler
self.asyncio_loop.add_reader(fd, self._handle_events, fd, IOLoop.READ)
File "/usr/lib/python3.8/asyncio/selector_events.py", line 332, in add_reader
return self._add_reader(fd, callback, *args)
File "/usr/lib/python3.8/asyncio/selector_events.py", line 261, in _add_reader
self._selector.register(fd, selectors.EVENT_READ,
File "/usr/lib/python3.8/selectors.py", line 359, in register
self._selector.register(key.fd, poller_events)
FileExistsError: [Errno 17] File exists
Traceback (most recent call last):
File "/usr/lib/python3.8/asyncio/selector_events.py", line 259, in _add_reader
key = self._selector.get_key(fd)
File "/usr/lib/python3.8/selectors.py", line 192, in get_key
raise KeyError("{!r} is not registered".format(fileobj)) from None
KeyError: '6 is not registered'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "../.config/JetBrains/PyCharmCE2020.2/scratches/scratch_1.py", line 12, in <module>
panel.serve(
File "/home/rick/panel/panel/io/server.py", line 208, in serve
server = get_server(panels, **kwargs)
File "/home/rick/panel/panel/io/server.py", line 380, in get_server
server = Server(apps, port=port, **opts)
File "/home/rick/.local/lib/python3.8/site-packages/bokeh/server/server.py", line 415, in __init__
http_server.add_sockets(sockets)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/tcpserver.py", line 165, in add_sockets
self._handlers[sock.fileno()] = add_accept_handler(
File "/home/rick/.local/lib/python3.8/site-packages/tornado/netutil.py", line 279, in add_accept_handler
io_loop.add_handler(sock, accept_handler, IOLoop.READ)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/platform/asyncio.py", line 100, in add_handler
self.asyncio_loop.add_reader(fd, self._handle_events, fd, IOLoop.READ)
File "/usr/lib/python3.8/asyncio/selector_events.py", line 332, in add_reader
return self._add_reader(fd, callback, *args)
File "/usr/lib/python3.8/asyncio/selector_events.py", line 261, in _add_reader
self._selector.register(fd, selectors.EVENT_READ,
File "/usr/lib/python3.8/selectors.py", line 359, in register
self._selector.register(key.fd, poller_events)
FileExistsError: [Errno 17] File exists
Traceback (most recent call last):
File "/usr/lib/python3.8/asyncio/selector_events.py", line 259, in _add_reader
key = self._selector.get_key(fd)
File "/usr/lib/python3.8/selectors.py", line 192, in get_key
raise KeyError("{!r} is not registered".format(fileobj)) from None
KeyError: '6 is not registered'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "../.config/JetBrains/PyCharmCE2020.2/scratches/scratch_1.py", line 12, in <module>
panel.serve(
File "/home/rick/panel/panel/io/server.py", line 208, in serve
server = get_server(panels, **kwargs)
File "/home/rick/panel/panel/io/server.py", line 380, in get_server
server = Server(apps, port=port, **opts)
File "/home/rick/.local/lib/python3.8/site-packages/bokeh/server/server.py", line 415, in __init__
http_server.add_sockets(sockets)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/tcpserver.py", line 165, in add_sockets
self._handlers[sock.fileno()] = add_accept_handler(
File "/home/rick/.local/lib/python3.8/site-packages/tornado/netutil.py", line 279, in add_accept_handler
io_loop.add_handler(sock, accept_handler, IOLoop.READ)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/platform/asyncio.py", line 100, in add_handler
self.asyncio_loop.add_reader(fd, self._handle_events, fd, IOLoop.READ)
File "/usr/lib/python3.8/asyncio/selector_events.py", line 332, in add_reader
return self._add_reader(fd, callback, *args)
File "/usr/lib/python3.8/asyncio/selector_events.py", line 261, in _add_reader
self._selector.register(fd, selectors.EVENT_READ,
File "/usr/lib/python3.8/selectors.py", line 359, in register
self._selector.register(key.fd, poller_events)
FileExistsError: [Errno 17] File exists
^XTraceback (most recent call last):
File "/usr/lib/python3.8/asyncio/selector_events.py", line 259, in _add_reader
key = self._selector.get_key(fd)
File "/usr/lib/python3.8/selectors.py", line 192, in get_key
raise KeyError("{!r} is not registered".format(fileobj)) from None
KeyError: '6 is not registered'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "../.config/JetBrains/PyCharmCE2020.2/scratches/scratch_1.py", line 12, in <module>
panel.serve(
File "/home/rick/panel/panel/io/server.py", line 208, in serve
server = get_server(panels, **kwargs)
File "/home/rick/panel/panel/io/server.py", line 380, in get_server
server = Server(apps, port=port, **opts)
File "/home/rick/.local/lib/python3.8/site-packages/bokeh/server/server.py", line 415, in __init__
http_server.add_sockets(sockets)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/tcpserver.py", line 165, in add_sockets
self._handlers[sock.fileno()] = add_accept_handler(
File "/home/rick/.local/lib/python3.8/site-packages/tornado/netutil.py", line 279, in add_accept_handler
io_loop.add_handler(sock, accept_handler, IOLoop.READ)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/platform/asyncio.py", line 100, in add_handler
self.asyncio_loop.add_reader(fd, self._handle_events, fd, IOLoop.READ)
File "/usr/lib/python3.8/asyncio/selector_events.py", line 332, in add_reader
return self._add_reader(fd, callback, *args)
File "/usr/lib/python3.8/asyncio/selector_events.py", line 261, in _add_reader
self._selector.register(fd, selectors.EVENT_READ,
File "/usr/lib/python3.8/selectors.py", line 359, in register
self._selector.register(key.fd, poller_events)
FileExistsError: [Errno 17] File exists
^CTraceback (most recent call last):
File "../.config/JetBrains/PyCharmCE2020.2/scratches/scratch_1.py", line 12, in <module>
panel.serve(
File "/home/rick/panel/panel/io/server.py", line 208, in serve
server = get_server(panels, **kwargs)
File "/home/rick/panel/panel/io/server.py", line 380, in get_server
server = Server(apps, port=port, **opts)
File "/home/rick/.local/lib/python3.8/site-packages/bokeh/server/server.py", line 414, in __init__
http_server.start(opts.num_procs)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/tcpserver.py", line 241, in start
process.fork_processes(num_processes, max_restarts)
File "/home/rick/.local/lib/python3.8/site-packages/tornado/process.py", line 148, in fork_processes
pid, status = os.wait()