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Reporting an issue with util.SizeEstimator, as requested.

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Assessment

Difficulty
4/5
Estimated time
3-5 days
Newbie friendliness
35/100
Issue type
Bug
Clarity
Needs clarification
Activity status
Active
Tech stack
java, python, scala, spark

Research direction

Start by identifying whether the reported IndexError comes from PySpark's Jupyter kernel event loop or from Spark's SizeEstimator warning; the report includes both outputs but no reproduction steps or expected behavior. Read the traceback entry points in ipykernel_launcher.py and Tornado's asyncio loop, then check whether the warning is related. Done means reproducing the failure and establishing which component owns it before proposing a fix.

Written by the indexing model from the issue text.

Description

WARNING: An illegal reflective access operation has occurred (0 + 8) / 8]
WARNING: Illegal reflective access by org.apache.spark.util.SizeEstimator$ (file:/usr/lib/spark/jars/spark-core_2.12-3.5.3.jar) to field java.lang.ref.Reference.referent
WARNING: Please consider reporting this to the maintainers of org.apache.spark.util.SizeEstimator$
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
Traceback (most recent call last):==================================(4 + 1) / 4]
File "", line 198, in _run_module_as_main
File "", line 88, in _run_code
File "/opt/conda/miniconda3/lib/python3.11/site-packages/ipykernel_launcher.py", line 18, in
app.launch_new_instance()
File "/opt/conda/miniconda3/lib/python3.11/site-packages/traitlets/config/application.py", line 1075, in launch_instance
app.start()
File "/opt/conda/miniconda3/lib/python3.11/site-packages/ipykernel/kernelapp.py", line 739, in start
self.io_loop.start()
File "/opt/conda/miniconda3/lib/python3.11/site-packages/tornado/platform/asyncio.py", line 211, in start
self.asyncio_loop.run_forever()
File "/opt/conda/miniconda3/lib/python3.11/asyncio/base_events.py", line 608, in run_forever
self._run_once()
File "/opt/conda/miniconda3/lib/python3.11/asyncio/base_events.py", line 1921, in _run_once
handle = self._ready.popleft()
^^^^^^^^^^^^^^^^^^^^^
IndexError: pop from an empty deque

Dominant language
Scala
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Merged PRs (30d)
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Getting set up

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

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