Ollama MLX Runner 10s Watchdog Timeout on Mac with Large Context — Fix Guide

What this error means

[Mac/MLX] MLX Runner killed by 10s watchdog timeout during large context prefill is a Ollama failure pattern reported for developers trying to fix ollama mlx runner being killed by 10-second watchdog timeout when processing large context windows on apple silicon mac. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub issue (2026-05-10) with detailed logs showing watchdog timeout regression. Specific to Apple Silicon MLX runner with large context windows. Affects popular use case (long-context LLM inference).

Common causes

• Since Ollama v0.23.1/v0.23.2, the MLX runner on Apple Silicon Macs is terminated by a strict 10-second heartbeat timeout during large context prefill (32k+ tokens) or slow-prefill MoE models. This causes 500 Internal Server Error, completely blocking long-context operations. v0.22.1 works fine — this is a regression.
• GitHub issue (2026-05-10) with detailed logs showing watchdog timeout regression. Specific to Apple Silicon MLX runner with large context windows. Affects popular use case (long-context LLM inference).

Quick fixes

1. Confirm the exact error signature matches [Mac/MLX] MLX Runner killed by 10s watchdog timeout during large context prefill.
2. Check the Ollama account, local tool state, and provider configuration involved in the failing workflow.
3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/ollama/ollama/issues/16081

Evidence note: GitHub issue (2026-05-10) with detailed logs showing watchdog timeout regression. Specific to Apple Silicon MLX runner with large context windows. Affects popular use case (long-context LLM inference).

Related errors

• Ollama 500 Internal Server Error Mac
• Ollama MLX context window timeout

FAQ

What should I check first?

Start with the exact [Mac/MLX] MLX Runner killed by 10s watchdog timeout during large context prefill text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed Ollama workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without [Mac/MLX] MLX Runner killed by 10s watchdog timeout during large context prefill.