Celery Redis not clearing out despite having

The Fix

pip install celery==5.0.0

Based on closed celery/celery issue #6240 · PR/commit linked

Production note: This usually shows up under retries/timeouts. Treat it as a side-effect risk until you can verify behavior with a canary + real traffic.

Jump to Verify Open PR/Commit

@@ -113,7 +113,7 @@ have been moved into a new  ``task_`` prefix.
 ``CELERY_RESULT_EXCHANGE``                 :setting:`result_exchange`
 ``CELERY_RESULT_EXCHANGE_TYPE``            :setting:`result_exchange_type`
-``CELERY_RESULT_EXPIRES``                  :setting:`result_expires`
+``CELERY_TASK_RESULT_EXPIRES``             :setting:`result_expires`
 ``CELERY_RESULT_PERSISTENT``               :setting:`result_persistent`

repro.py

from celery import Celery

CONFIG = {
    'BROKER_URL': 'redis://localhost:6379/0',
    'CELERY_RESULT_BACKEND': 'redis://localhost:6379/0',
    'CELERY_RESULT_EXPIRES': 15, # 15 secs
    'BROKER_POOL_LIMIT': 0, # redis connection get closed once task is done..
}


celery = Celery('tasks', config_source=CONFIG)

@celery.task(name='tasks.say_hello')
def say_hello():
    return "Helloooooo i just came out from the background!"


if __name__ == '__main__':
    say_hello.delay().get()

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

fix.md

Option A — Upgrade to fixed release\npip install celery==5.0.0\nWhen NOT to use: This fix is not applicable if the documentation is already correct or if using a different configuration method.\n\n

Why This Fix Works in Production

Trigger: - [x] I have included all related issues and possible duplicate issues
Mechanism: The configuration documentation incorrectly referenced `CELERY_RESULT_EXPIRES` instead of `CELERY_TASK_RESULT_EXPIRES`
Why the fix works: Corrects the configuration documentation from `CELERY_RESULT_EXPIRES` to `CELERY_TASK_RESULT_EXPIRES` to resolve issue #6240. (first fixed release: 5.0.0).

Production impact:

If left unfixed, the same config can fail only in production (env differences), causing startup failures or partial feature outages.

Why This Breaks in Prod

The configuration documentation incorrectly referenced `CELERY_RESULT_EXPIRES` instead of `CELERY_TASK_RESULT_EXPIRES`
Production symptom (often without a traceback): - [x] I have included all related issues and possible duplicate issues

Proof / Evidence

GitHub issue: #6240
Fix PR: https://github.com/celery/celery/pull/6303
First fixed release: 5.0.0
Reproduced locally: No (not executed)
Last verified: 2026-02-09
Confidence: 0.85
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.54

Discussion

High-signal excerpts from the issue thread (symptoms, repros, edge-cases).

Jump to Sources Open on GitHub

“The docs are wrong, it says for celery 4.x. CELERY_RESULT_EXPIRES implies result_expires but its CELERY_TASK_RESULT_EXPIRES which got it to work.”

@bonkstonk · 2020-07-25 · source

“can you send a PR for improving the doc?”

@auvipy · 2020-07-26 · source

Failure Signature (Search String)

- [x] I have included all related issues and possible duplicate issues
or possible duplicates to this issue as requested by the checklist above.

Copy-friendly signature

signature.txt

Failure Signature
-----------------
- [x] I have included all related issues and possible duplicate issues
or possible duplicates to this issue as requested by the checklist above.

Error Message

Signature-only (no traceback captured)

error.txt

Error Message
-------------
- [x] I have included all related issues and possible duplicate issues
or possible duplicates to this issue as requested by the checklist above.

Minimal Reproduction

repro.py

from celery import Celery

CONFIG = {
    'BROKER_URL': 'redis://localhost:6379/0',
    'CELERY_RESULT_BACKEND': 'redis://localhost:6379/0',
    'CELERY_RESULT_EXPIRES': 15, # 15 secs
    'BROKER_POOL_LIMIT': 0, # redis connection get closed once task is done..
}


celery = Celery('tasks', config_source=CONFIG)

@celery.task(name='tasks.say_hello')
def say_hello():
    return "Helloooooo i just came out from the background!"


if __name__ == '__main__':
    say_hello.delay().get()

What Broke

Redis does not clear out results as expected, leading to potential data retention issues.

Why It Broke

The configuration documentation incorrectly referenced `CELERY_RESULT_EXPIRES` instead of `CELERY_TASK_RESULT_EXPIRES`

Fix Options (Details)

Option A — Upgrade to fixed release Safe default (recommended)

pip install celery==5.0.0

When NOT to use: This fix is not applicable if the documentation is already correct or if using a different configuration method.

Use when you can deploy the upstream fix. It is usually lower-risk than long-lived workarounds.

Fix reference: https://github.com/celery/celery/pull/6303

First fixed release: 5.0.0

Last verified: 2026-02-09. Validate in your environment.

When NOT to Use This Fix

This fix is not applicable if the documentation is already correct or if using a different configuration method.

Verify Fix

verify

Re-run the minimal reproduction on your broken version, then apply the fix and re-run.

Did This Fix Work in Your Case?

Quick signal helps us prioritize which fixes to verify and improve.

Prevention

Capture the exact failing error string in logs and tests so you can reproduce via a minimal script.
Pin production dependencies and upgrade only with a reproducible test that hits the failing path.

Version Compatibility Table

Version	Status
5.0.0	Fixed

Related Issues

No related fixes found.

Cluster: celery:configuration-error Celery hub Celery best practices All hubs All clusters

Related clusters: Data consistency Duplicates Duplicate processing

Sources

We don’t republish the full GitHub discussion text. Use the links above for context.

Celery Redis not clearing out despite having `CELERY_RESULT_EXPIRES` configuration (Fix)