Possible Deadlock on loading model with LOCALAI_SINGLE_ACTIVE_BACKEND=true

[richiejp]

LocalAI version:
localai/localai master-sycl-f32-ffmpeg-core 80b00526012e (after v2.28)

Environment, CPU architecture, OS, and Version:
Linux sys76 6.6.88 #1-NixOS SMP PREEMPT_DYNAMIC Fri Apr 25 08:45:59 UTC 2025 x86_64 GNU/Linux

Describe the bug
When attempting to read transcription endpoint only the message stating the file was copied is shown. After that there should be more log messages if it gets any further, but it appears to get stuck or freeze while taking the singleton lock. Of course I could be missing something.

The completions endpoint produces more logs, but also got stuck before loading the model.

To Reproduce

Just tried to use transcription. Not clear if it is reproducible.

Additional context

If I am correct and it is deadlocking on the singleton lock then unsetting LOCALAI_SINGLE_ACTIVE_BACKEND will work around it