Fix /shuffle dashboard with in-memory storage

[hendrikmakait]

Fixes

bokeh.util.tornado - ERROR - Traceback (most recent call last):
  File "/opt/coiled/env/lib/python3.11/site-packages/tornado/gen.py", line 530, in callback
    result_list.append(f.result())
                       ^^^^^^^^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/bokeh/server/session.py", line 94, in _needs_document_lock_wrapper
    result = func(self, *args, **kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/bokeh/server/session.py", line 226, in with_document_locked
    return func(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/bokeh/document/callbacks.py", line 485, in wrapper
    return invoke_with_curdoc(doc, invoke)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/bokeh/document/callbacks.py", line 443, in invoke_with_curdoc
    return f()
           ^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/bokeh/document/callbacks.py", line 484, in invoke
    return f(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/distributed/dashboard/components/__init__.py", line 41, in <lambda>
    doc.add_periodic_callback(lambda: update(ref), interval)
                                      ^^^^^^^^^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/bokeh/core/property/validation.py", line 95, in func
    return input_function(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/distributed/dashboard/components/__init__.py", line 49, in update
    comp.update()
  File "/opt/coiled/env/lib/python3.11/site-packages/bokeh/core/property/validation.py", line 95, in func
    return input_function(*args, **kwargs)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/coiled/env/lib/python3.11/site-packages/distributed/dashboard/components/scheduler.py", line 4476, in update
    elif d[prefix]["memory"] > d[prefix]["memory_limit"]:
         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TypeError: '>' not supported between instances of 'int' and 'NoneType'

• Tests added / passed
• Passes pre-commit run --all-files

[github-actions]

Unit Test Results

See test report for an extended history of previous test failures. This is useful for diagnosing flaky tests.

       27 files  ±0         27 suites  ±0   15h 41m 5s ⏱️ - 19m 58s
  3 932 tests ±0    3 812 ✔️ +3     115 💤 ±0    5 ❌  - 3 
49 387 runs  ±0  47 019 ✔️ +5  2 341 💤 ±0  27 ❌  - 5 

For more details on these failures, see this check.

Results for commit 44400ec. ± Comparison against base commit 095a09d.

[crusaderky]

would it be reasonable to add a test for it?

[hendrikmakait]

would it be reasonable to add a test for it?

In principle, yes, in practice, I'd like to add general testing for the dashboard in a follow-up.

[milesgranger]

Good for me! 👍