# DistributedMutex error warnings frequently appearing in logs

**URL:** <https://meta.discourse.org/t/distributedmutex/402855>\
**Category:** Support\
**Created:** [May 13, 2026, 11:19am UTC](https://meta.discourse.org/t/distributedmutex/402855 "2026-05-13T11:19:44Z")\
**Posts on this page:** 1\
**Showing post:** 2

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**Author:** ![Ethsim2](https://sea3.discourse-cdn.com/meta/user_avatar/meta.discourse.org/ethsim2/32/522255_2.png) [@Ethsim2](https://meta.discourse.org/u/Ethsim2)\
**Post date:** [May 13, 2026, 2:28pm UTC](https://meta.discourse.org/t/distributedmutex/402855/2 "2026-05-13T14:28:41Z")

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This is probably not caused directly by the reverse proxy.

For API-created posts, Discourse uses `DistributedMemoizer` around `PostsController#create` to avoid duplicate API post creation. That memoizer uses a Redis-backed `DistributedMutex` with a very short validity time of 1 second. The warning means that the post creation / serialization work inside that lock took longer than expected.

So:

- if the API post is still created successfully, this is a warning rather than the root failure;
- `expected max: 1 secs, took an extra 1 secs` means the lock was held for roughly 2 seconds;
- it is more likely related to server performance, Redis/Postgres latency, disk I/O, CPU/RAM pressure, plugins, or slow post-processing than to nginx/1Panel reverse proxy itself;
- the reason it only appears for API posting is that this memoizer path is used for API requests.

Things worth checking:

1. Does the API request succeed and create only one post?
2. How long does the API request take from the client side?
3. Are CPU, memory, swap, or disk I/O saturated during API posting?
4. Are Redis and Postgres inside the same container/host, and are they healthy?
5. Does the warning still happen with a very small plain-text post and no images/uploads?
6. Are there non-standard plugins installed?

Since this is a 1Panel/container deployment rather than the standard Discourse Docker install, it may also be useful to reproduce on an official supported install if possible before treating it as a Discourse core bug.

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