Application hangs if running with a single CPU allocated

[fabasoad]

Describe the bug
I've discovered this problem with my colleague when we ran ottoopensource/gitactionboard docker image in our k8s cluster. The default resources allocation was with a single CPU. But it is easy to reproduce it with docker/podman.

To Reproduce
Steps to reproduce the behavior:

1. Run the command below.

   podman run --rm -e REPO_OWNER_NAME=otto-de -e REPO_NAMES=gitactionboard -p 8080:8080 --cpus=1 -it 
   ottoopensource/gitactionboard:latest

2. Go to localhost:8008 in your web browser

3. Be sure that it is loading forever

4. Look at logs and be sure that it hangs

5. Stop the process

6. Run the command below.

   podman run --rm -e REPO_OWNER_NAME=otto-de -e REPO_NAMES=gitactionboard -p 8080:8080 --cpus=2 -it 
   ottoopensource/gitactionboard:latest

7. Go to localhost:8008 in your web browser

8. Be sure that all workflows have been loaded successfully

9. Look at logs and be sure that nothing hangs

Expected behavior
I think one of the options is fine:

• (Preference 1) Make it work even on a single CPU
• (Preference 2) Handle the situation when application hangs and throw a clear message after some timeout that application lacks of resources
• (Preference 3) Document somewhere machine requirements (minimum CPU, RAM, etc.)

Screenshots

Step 3:

Step 8:

Logs

Step 4:

logs-1.txt

Step 9:

logs-2.txt

Additional context
We've spend with my colleague a few hours to understand what was the problem of not loading the data started with debugging k8s cluster and ended up reading source code of otto-de/gitactionboard where we found CompletableFuture usage in GithubWorkflowService. Handling this situation with timeout or at least documenting resources requirements would save us some time and I hope it will save time for people in a future who might face the same problem. Thank you.

[boring-cyborg]

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