Internal curl errors has occurred within the executor

Hi, I am trying to figure out how to scale a function (multiple workers for a single function), but it doesn't run very stable. Some executions run fine but some don't, as you can see in the attached screenshot. I have duplicated the appwrite-worker-functions container 4 times, so I have a total of 5 appwrite-worker-functions containers. When I use a single worker-function container, everything works perfectly. But when I add more worker-function containers, some executions fail with the error Internal curl errors has occurred within the executor! Error Number: 110. Error Msg: Operation timed out\nError Code: 500. The openruntime-executor container logs are the following:

[Error] Type: Exception
[Error] Message: Internal curl errors has occurred within the executor! Error Number: 110. Error Msg: Operation timed out
[Error] File: /usr/local/app/http.php
[Error] Line: 1072

The docker-compose part of the worker-functions containers looks like this:

appwrite-worker-functions-1:
  image: appwrite/appwrite:1.5.7
  entrypoint: worker-functions
  # <<: *x-logging
  container_name: appwrite-worker-functions-1
  restart: unless-stopped
  # networks:
  #   - appwrite
  depends_on:
    - appwrite-redis
    - appwrite-mariadb
    - openruntimes-executor
  environment:
    - _APP_ENV
    - ... more envs
  
appwrite-worker-functions-2:
  image: appwrite/appwrite:1.5.7
  entrypoint: worker-functions
  # <<: *x-logging
  container_name: appwrite-worker-functions-2
  restart: unless-stopped
  # networks:
  #   - appwrite
  depends_on:
    - appwrite-redis
    - appwrite-mariadb
    - openruntimes-executor
  environment:
    - _APP_ENV
    - ... more envs

...+ 3 more worker-functions 
containers

I have set _APP_FUNCTIONS_CPUS to the default of 0 and _APP_WORKER_PER_CORE to the default of 6. I am using Appwrite self-hosted v1.5.7.

Any idea what would cause this issue? Or am I missing something here?