--- title: FAQ description: Frequently asked questions --- **Q: The trainer stopped and hasn't progressed in several minutes.** > A: Usually an issue with the GPUs communicating with each other. See the [NCCL doc](nccl.qmd) **Q: Exitcode -9** > A: This usually happens when you run out of system RAM. **Q: Exitcode -7 while using deepspeed** > A: Try upgrading deepspeed w: `pip install -U deepspeed` **Q: AttributeError: 'DummyOptim' object has no attribute 'step'** > A: You may be using deepspeed with single gpu. Please don't set `deepspeed:` in yaml or cli.