Why is Ollama so slow?
“Slow” can mean a long wait before the first token, slow token generation, or a model that is repeatedly loading and unloading. Identify which one you have before changing settings.
1. Check processor placement
Start a model, then run this in a second terminal:
ollama ps
If the output includes a processor column, check whether the model is on CPU, GPU or split between them. The answer helps decide whether to investigate driver support or memory pressure first.
2. Compare with a smaller installed model
ollama list
Try a smaller model you already have. If it responds much faster, the larger model may simply need more compute or memory. Model size alone is not a perfect speed predictor.
3. Notice context length
Long conversations and large context windows can increase memory use and affect performance. For a fair test, start a fresh conversation with a short prompt, and compare the same prompt across models.
4. Check other workloads
Close games, GPU-heavy applications or other model servers temporarily. For NVIDIA, nvidia-smi can show processes and GPU memory use. Other vendors have their own monitoring tools.
5. Use a repeatable test
- Restart Ollama and let the machine settle.
- Run the same short prompt with the same model.
- Note the delay before the first response and the generation speed.
- Repeat with a smaller model and compare.
A single speed number without the model, quantization, context and hardware is not very meaningful.
Official reference: Ollama documentation.