redis-py Unexpected keyword argument 'retry' when using

The Fix

Fixes an issue with the 'retry' attribute in UnixDomainSocketConnection, resolving the TypeError encountered when using unix socket connections.

Based on closed redis/redis-py issue #1601 · PR/commit linked

Production note: Most teams hit this during upgrades or environment changes. Roll out with a canary and smoke critical endpoints (health, OpenAPI/docs) before 100%.

Jump to Verify Open PR/Commit

@@ -880,7 +880,13 @@ def __init__(self, path='', db=0, username=None, password=None,
                  retry_on_timeout=False,
                  parser_class=DefaultParser, socket_read_size=65536,
-                 health_check_interval=0, client_name=None):
+                 health_check_interval=0, client_name=None,
+                 retry=None):

repro.py

1196             raise ConnectionError("Too many connections")
   1197         self._created_connections += 1
-> 1198         return self.connection_class(**self.connection_kwargs)
   1199 
   1200     def release(self, connection):

TypeError: __init__() got an unexpected keyword argument 'retry'

verify

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

fix.md

Option A — Apply the official fix\nFixes an issue with the 'retry' attribute in UnixDomainSocketConnection, resolving the TypeError encountered when using unix socket connections.\nWhen NOT to use: This fix should not be used if the application does not require retry functionality.\n\n

Why This Fix Works in Production

Trigger: 1196 raise ConnectionError("Too many connections")
Mechanism: The UnixDomainSocketConnection class did not accept a 'retry' argument, causing a TypeError

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 UnixDomainSocketConnection class did not accept a 'retry' argument, causing a TypeError
Surfaces as: 1196 raise ConnectionError("Too many connections")

Proof / Evidence

GitHub issue: #1601
Fix PR: https://github.com/redis/redis-py/pull/1604
Reproduced locally: No (not executed)
Last verified: 2026-02-12
Confidence: 0.70
Did this fix it?: Yes (upstream fix exists)
Own content ratio: 0.49

Discussion

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

Jump to Sources Open on GitHub

“**redis-py 3.9.9, redis 6.2.6** When I tried to use unix socket connection: I got error: almost same using UnixDomainSocketConnection:”

Issue thread · issue description · source

Failure Signature (Search String)

1196 raise ConnectionError("Too many connections")

Error Message

Stack trace

error.txt

Error Message
-------------
1196             raise ConnectionError("Too many connections")
   1197         self._created_connections += 1
-> 1198         return self.connection_class(**self.connection_kwargs)
   1199 
   1200     def release(self, connection):

TypeError: __init__() got an unexpected keyword argument 'retry'

Stack trace

error.txt

Error Message
-------------
1035         try:
-> 1036             return conn.retry.call_with_retry(
   1037                 lambda: self._send_command_parse_response(conn,
   1038                                                           command_name,

AttributeError: 'UnixDomainSocketConnection' object has no attribute 'retry'

Minimal Reproduction

repro.py

1196             raise ConnectionError("Too many connections")
   1197         self._created_connections += 1
-> 1198         return self.connection_class(**self.connection_kwargs)
   1199 
   1200     def release(self, connection):

TypeError: __init__() got an unexpected keyword argument 'retry'

What Broke

Users experienced TypeErrors when attempting to connect via Unix socket.

Why It Broke

The UnixDomainSocketConnection class did not accept a 'retry' argument, causing a TypeError

Fix Options (Details)

Option A — Apply the official fix

Fixes an issue with the 'retry' attribute in UnixDomainSocketConnection, resolving the TypeError encountered when using unix socket connections.

When NOT to use: This fix should not be used if the application does not require retry functionality.

Fix reference: https://github.com/redis/redis-py/pull/1604

Last verified: 2026-02-12. Validate in your environment.

When NOT to Use This Fix

This fix should not be used if the application does not require retry functionality.

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

Track RSS + object counts after deployments; alert on monotonic growth and GC pressure.
Add a long-running test that repeats the failing call path and asserts stable memory.

Related Issues

No related fixes found.

Cluster: redis-py:configuration-error redis-py hub redis-py best practices All hubs All clusters

Related clusters: Retry storm Data consistency Race condition

Sources

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

redis-py Unexpected keyword argument 'retry' when using unix socket (Fix)