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Celery Production Incidents & Fixes

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Grouped incident families for Celery (use these when you’re debugging during an outage).

Configuration error

issues: 174 fresh: 39 indexable

Data consistency

issues: 42 fresh: 12 indexable

Duplicates

issues: 21 fresh: 5 indexable

Duplicate processing

issues: 6 fresh: 4 indexable

Auth

issues: 7 fresh: 2 indexable

Top Queries / Error Strings

These are the lines developers tend to paste into Google during incidents.

or possible duplicates to this issue as requested by the checklist above.

.> celery exchange=celery(direct) key=celery

KeyError: 'collection'

async-timeout==4.0.2

$ celery -A proj multi start worker1 --template foo

$ poetry run python celery_bug.py

$ python ./manage.py shell

'traceback': traceback,

(celery) ➜ myapp git:(master) ./manage.py test_cmd

).on_error(f2).apply_async()

Watch Celery

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Celery worker OOM due to unbounded prefetch on eta tasks

#9849 · celery/celery

Unlike what doc states, --app does not behave like -A

#4558 · celery/celery

Celery hangs indefinitely (instead of failing) if redis is not started

#4556 · celery/celery

Task.retry() always raises RuntimeError if task_always_eager and task_eager_propagates are set

#4661 · celery/celery

Celery timezone use default UTC timezone ignoring settings.

#4842 · celery/celery

Redis results backend: apply_async().get() hangs forever after disconnection from redis-server

#4857 · celery/celery

SQS MessageDeduplicationId

#5281 · celery/celery

Why has the CLI worker command flag `optimizations` changed from `--optimizations` in 5.*?

#8224 · celery/celery

Ctrl-C Does not properly Kill the celery interactive process

#8282 · celery/celery

After celery lib upgrade to 5.3.3, get sql exception.

#8470 · celery/celery

[5.3.0] Task results order is not preserved anymore

#8421 · celery/celery

Invalid format of 'date_done' field in celery.task_results with backend mongodb

#8431 · celery/celery

Task is requeued with compression header but the body is not compressed

#8625 · celery/celery

Getting Started has Circular Import Issue

#8561 · celery/celery

Error "Recursive result parents" on some tasks trees

#8890 · celery/celery

Memory Leak on Unhandled Exceptions

#8882 · celery/celery

AttributeError: 'DisabledBackend' object has no attribute '_restore_group'

#9006 · celery/celery

Cannot disconnect a signal receiver after using Signal.connect(retry=True)

#9119 · celery/celery

Missing Import in Documentation in Django tutorial

#9098 · celery/celery

Missing CPendingDeprecationWarning from Celery v5.4.0

#9383 · celery/celery

_maybe_close_db_fd in Django fixups does not correctly handle all exceptions

#9310 · celery/celery

django example does not run

#9431 · celery/celery

RedisBackend does not retry on store_result even with result_backend_always_retry=True

#9613 · celery/celery

Celery does not respect the redis-py version bounds specified by kombu (redis-py 5.3.0 was released)

#9680 · celery/celery

Task acks on Hard Timeout when `task_acks_on_failure_or_timeout` is `False`

#9596 · celery/celery

Group results aren't cleaned up on result.forget() - memory leak

#9797 · celery/celery

chord of chains with groups: body duplication and invalid task execution order

#5947 · celery/celery

TypeError in make_connection, unexpected keyword argument 'socket_keepalive'

#5994 · celery/celery

Memory leak in Exception Task with Prefork(worker)

#6023 · celery/celery

Unable to use mysql SSL parameters in create_engine()

#6019 · celery/celery

Memory leak after task raise exception

#6058 · celery/celery

support for quorum queues

#6067 · celery/celery

Missing dependency on future in 4.4.4

#6145 · celery/celery

Celery 4.4.4 raises TypeError: set() takes 3 positional arguments but 4 were given

#6155 · celery/celery

CELERY_DB_REUSE_MAX possibly broken by #6134

#6216 · celery/celery

flakey test test_chord.test_add_chord_to_chord

#6256 · celery/celery

Celery 4.4.7 attempts to use amqp despite being given Redis broker_url & result_backend

#6370 · celery/celery

AsyncResult memory leak on task producers

#6772 · celery/celery

Celery breaks libs using `sys.stdout.write()`

#6790 · celery/celery

using couchdb backend throws TypeError: a bytes-like object is required, not 'str'

#6781 · celery/celery

Chord across multiple apps using signatures breaks on task not registered

#6846 · celery/celery

ProxyLogger.write raises TypeError due to rstrip on a bytes instance.

#7056 · celery/celery

Start celery in the detached mode

#7200 · celery/celery