404 GET /dask/dashboard/... in console

[dipbasu]

When shutting down a LocalCluster I receive 404 GET /dask/dashboard/.../individual-plots.json? messages in the console window E.g.

[W 09:30:37.716 LabApp] 404 GET /dask/dashboard/e928b78c-1bb6-4a99-92f1-7c32e4f05071/individual-plots.json?1609925437712 (::1) 1.440000ms referer=http://localhost:8888/lab
[W 09:30:41.721 LabApp] 404 GET /dask/dashboard/e928b78c-1bb6-4a99-92f1-7c32e4f05071/individual-plots.json?1609925441717 (::1) 1.450000ms referer=http://localhost:8888/lab
[W 09:30:45.728 LabApp] 404 GET /dask/dashboard/e928b78c-1bb6-4a99-92f1-7c32e4f05071/individual-plots.json?1609925445724 (::1) 1.340000ms referer=http://localhost:8888/lab
[W 09:30:49.733 LabApp] 404 GET /dask/dashboard/e928b78c-1bb6-4a99-92f1-7c32e4f05071/individual-plots.json?1609925449729 (::1) 1.290000ms referer=http://localhost:8888/lab
[W 09:30:53.740 LabApp] 404 GET /dask/dashboard/e928b78c-1bb6-4a99-92f1-7c32e4f05071/individual-plots.json?1609925453736 (::1) 1.330000ms referer=http://localhost:8888/lab
[W 09:30:57.746 LabApp] 404 GET /dask/dashboard/e928b78c-1bb6-4a99-92f1-7c32e4f05071/individual-plots.json?1609925457742 (::1) 1.330000ms referer=http://localhost:8888/lab

If I restart jupyter lab, these messages continue appear even when I am not working with dask.

They stop if I start a new cluster but they reappear if the cluster is shutdown again.

It's not a big issue but more of an annoyance as I may miss important messages in the console as the warning repeats every two seconds.

I suspect it is related to how the dask-dashboard-launcher entry in the lab-xxx.jupyterlab-workspace file (located in .jupyter/lab/workspaces) is used. E.g.

"dask-dashboard-launcher": {
            "url": "http://localhost:8888/dask/dashboard/e928b78c-1bb6-4a99-92f1-7c32e4f05071",
            "cluster": "00566038-4b2d-4b95-b482-455f07eaa996"
        }

Environment:

• Dask version: 2.11.0
• Python version: 3.8
• Operating System: MacOS
• Install method: Conda

Let me know if you require further information

[jacobtomlinson]

This is the Lab Extension polling for a Dask cluster and isn't really avoidable.

I think if you go to the Dask tab and clear the URL this will stop.

I wonder if we should also consider making this an exponential back off with a cap, to at least reduce the frequency this happens at.

[dipbasu]

Thanks for the update Jacob.

I've tried clearing the URL but this doesn't prevent the messages from appearing, even after restarting jupyter lab.

Is this something that appears with MacOS environments? My Windows 10 environment doesn't seem to have this behaviour when I start then shutdown local dask clusters.

[jacobtomlinson]

Is this something that appears with MacOS environments? My Windows 10 environment doesn't seem to have this behaviour when I start then shutdown local dask clusters.

It shouldn't make a difference. Are you running the same version of the lab extension?

[dipbasu]

In MacOS, I am running dask-labextension=2.0.1 and in Win10 dask-labextension=2.0.0
(I downgraded the MacOS library to use 2.0.0 but this made no difference.)

Is there anything else you can suggest I could try?

Environments
Windows 10
dask=2.11.0=py_0
dask-core=2.11.0=py_0
dask-labextension=2.0.0=py_0

Mac OS
dask 2.11.0 py_0
dask-core 2.11.0 py_0
dask-labextension 2.0.0 py_0

[jacobtomlinson]

Could you update to a more recent version? Latest is 4.0.1.

[dipbasu]

I've tried updating to 4.0.1 but it make no difference. I still observe these warnings:

[I 18:07:42.917 LabApp] Build is up to date
[W 18:07:43.392 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042862926 (::1) 238.690000ms referer=http://localhost:8888/lab
|[I 18:07:43.875 LabApp] Kernel started: 0b856984-426e-4e7f-8800-4dd5f85a4ef8, name: python3
[W 18:07:46.700 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042866695 (::1) 3.000000ms referer=http://localhost:8888/lab
[W 18:07:50.710 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042870704 (::1) 1.610000ms referer=http://localhost:8888/lab
[W 18:07:54.716 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042874712 (::1) 1.360000ms referer=http://localhost:8888/lab
[W 18:07:58.724 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042878720 (::1) 1.520000ms referer=http://localhost:8888/lab
[W 18:08:02.733 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042882729 (::1) 1.260000ms referer=http://localhost:8888/lab
[W 18:08:06.740 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042886735 (::1) 1.380000ms referer=http://localhost:8888/lab
[W 18:08:10.749 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042890745 (::1) 1.410000ms referer=http://localhost:8888/lab
[W 18:08:14.755 LabApp] 404 GET /dask/dashboard/ef9c0ae6-2348-4d3c-a288-6dce7ba1b409/individual-plots.json?1610042894751 (::1) 1.400000ms referer=http://localhost:8888/lab

I'll do some further investigation and see if I can replicate this behaviour on another Win10 virtual environment to see if it is potentially an OS related issue.

[rmalouf]

I have the same problem (dask-labextension 4.0.1 running in an ubuntu-based container on a centos server, connected via opera on macos). Clearing the dask dashboard url, as suggested above, doesn't stop it but it does change the message to:

[W 18:39:00.084 LabApp] 404 GET /individual-plots.json?1610303940078 (192.168.1.44) 2.300000ms referer=http://192.168.1.5:8888/lab?

[maximyudayev]

++ to the issue on LocalCluster. I would idolize the MVP who can point out what I did wrong. Thank you in advance.

Environment used pip for all the installs
jupyterlab==3.0.5
dask==2021.2.0
dask-labextension==5.0.0
node (v14.16.0) used curl -sL https://deb.nodesource.com/setup_14.x | sudo -E bash -
npm (v6.14.1)

Installed for the first time on Linux Mint: Linux maxim-UX21A 5.4.0-66-generic #74-Ubuntu SMP Wed Jan 27 22:54:38 UTC 2021 x86_64 x86_64 x86_64 GNU/Linux

404 errors from these URLs: (unlike @dipbasu, error comes from ServerApp, not LabApp)

[W 2021-02-27 23:46:48.628 ServerApp] 404 GET /dask/clusters?1614466007366 (127.0.0.1) 913.32ms referer=http://localhost:8888/lab
[W 2021-02-27 23:47:31.868 ServerApp] 404 GET /127.0.0.1:8787/individual-plots.json?1614466051859 (127.0.0.1) 3.08ms referer=http://localhost:8888/lab/tree/Documents/Master%20Thesis%20and%20ML/vsc/data_preprocessing.ipynb
[W 2021-02-27 23:47:32.606 ServerApp] 404 GET /dask/dashboard-check/http%3A%2F%2F127.0.0.1%3A8787?1614466052600 (127.0.0.1) 1.45ms referer=http://localhost:8888/lab/tree/Documents/Master%20Thesis%20and%20ML/vsc/data_preprocessing.ipynb

When clicking "New" in the Dask panel, nothing happens same when entering LocalCluster URL. Dashboard is visible at the IP address returned after initializing cluster by

from dask.distributed import Client
client = Client()
client

All the extensions appear to be enabled and work

$ jupyter serverextension list
config dir: /home/maxim/.jupyter
    dask_labextension  enabled 
    - Validating...
      dask_labextension 5.0.0 OK
    jupyter_server_proxy  enabled 
    - Validating...
      jupyter_server_proxy  OK
    jupyterlab  enabled 
    - Validating...$ jupyter labextension list
JupyterLab v3.0.5
/home/maxim/.local/share/jupyter/labextensions
        dask-labextension v5.0.0 enabled OK (python, dask_labextension)
        @jupyter-widgets/jupyterlab-manager v3.0.0 enabled OK (python, jupyterlab_widgets)

Other labextensions (built into JupyterLab)
   app dir: /home/maxim/.local/share/jupyter/lab

      jupyterlab 3.0.5 OK

$ jupyter labextension list
JupyterLab v3.0.5
/home/maxim/.local/share/jupyter/labextensions
        dask-labextension v5.0.0 enabled OK (python, dask_labextension)
        @jupyter-widgets/jupyterlab-manager v3.0.0 enabled OK (python, jupyterlab_widgets)

Other labextensions (built into JupyterLab)
   app dir: /home/maxim/.local/share/jupyter/lab

I open JupyterLab with $ jupyter lab and when jupyter loads, as the first thing receive a screen notification: