Workers created by `LocalCluster` have dashboards disabled by default

[jacobtomlinson]

When starting a cluster with LocalCluster it appears that the workers have their dashboards disabled by default as the default worker_dashboard_address is None.

distributed/distributed/deploy/local.py

Line 177 in f2b09c6

"dashboard": worker_dashboard_address is not None,

This is counter to starting a worker from the command line where the dashboard is enabled by default.

Setting the worker_dashboard_address to 0 in LocalCluster results in the dashboard running on a random high port. This is the same behaviour as the command line.

cluster = LocalCluster(worker_dashboard_address=0)

Therefore I propose we change the default value for worker_dashboard_address in LocalCluster to 0. User's can still disable the dashboard by explicitly setting worker_dashboard_address to None.

[mrocklin]

That's fine with me. My guess is that this was turned off due to profiling at some point, but I honestly don't recall. The worker dashboard isn't that commonly used today. I would be curious what people are doing with it. My guess is that they're mostly clicking on the "dashboard" button in the info pages out of curiosity, take a look around, and then don't do much else. If this request is generated out of that workflow then I think that we might pass. However if there are people genuinely wanting to use that data then great, let's turn the dashboards back on.

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On Thu, Jun 11, 2020 at 4:23 AM Jacob Tomlinson ***@***.***> wrote: When starting a cluster with LocalCluster it appears that the workers have their dashboards disabled by default as the default worker_dashboard_address is None. https://github.com/dask/distributed/blob/f2b09c6b55188f6b633cba5422454b689b0fd7b4/distributed/deploy/local.py#L177 This is counter to starting a worker from the command line where the dashboard is enabled by default <https://docs.dask.org/en/latest/setup/cli.html#cmdoption-dask-worker-dashboard> . Setting the worker_dashboard_address to 0 in LocalCluster results in the dashboard running on a random high port. This is the same behaviour as the command line. cluster = LocalCluster(worker_dashboard_address=0) Therefore I propose we change the default value for worker_dashboard_address in LocalCluster to 0. User's can still disable the dashboard by explicitly setting worker_dashboard_address to None. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#3884>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACKZTHZIXU3Q4WVFISWCE3RWC5DHANCNFSM4N3KHMCA> .

[jacobtomlinson]

The request came in from gitter and it sounded like they really wanted the information from the dashboard

[mrocklin]

Then fire away. If you're able to get what information they were after and elevate that to github somewhere (maybe even just as a comment to this issue) that would be, I think, educational.

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On Thu, Jun 11, 2020 at 8:33 AM Jacob Tomlinson ***@***.***> wrote: The request came in from gitter and it sounded like they really wanted the information from the dashboard — You are receiving this because you commented. Reply to this email directly, view it on GitHub <#3884 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AACKZTFK6QUUGEOARO3NWVTRWD2N7ANCNFSM4N3KHMCA> .

[jacobtomlinson]

@odovad could you share what you were looking to use the worker dashboard for?

[odovad]

@jacobtomlinson I use a KubeCluster and wanted to be able to have everything from the scheduler's dashboard directly inside Jupyterlab thanks to the jupyterlab dask-extension.
If I'm not mistaken, it involves the same mechanisms (proxy) than the worker's dashboard.
I never used the worker dashboard, I was also a little curious about it.

[jsignell]

I clarified this behavior in #4047, but didn't change it

[ncclementi]

Checking in here, Do we have a specific reason why the worker's dashboard is turned off by default?
I found that the info to turn it on is only in the docstrings and I wanted to add how to turn it on on the Workers page of the docs but it was pointed as an option to set it on as a default.
See #5373 (comment)

Any opinion on how to go about this?