Training appears to “crash” on Windows without any error, SOLVED

[Wernervanrun]

Summary

When running Kohya training on Windows, users may see GPU activity drop to zero and logs stop without any error messages. In most cases, this “crash” is actually the result of the console’s QuickEdit (text‑selection) mode pausing the process. Clearing the selection immediately resumes training.

Background & Cause

Windows’ built‑in console host (CMD, PowerShell) features a QuickEdit mode that lets you click and drag to select text. Entering selection mode blocks all console write operations—including the logging calls and the main loop that dispatches new GPU work—so it appears as if training has hung or crashed. In reality, the process is simply waiting for the selection to be cleared.

Steps to Reproduce

1. Launch Kohya training in a Windows CMD or PowerShell window.
2. Observe normal GPU activity in Task Manager.
3. Click inside the console to select any character.
4. Notice that GPU utilization drops to zero and logs stop.
5. Right‑click (or press Esc) to clear the selection—training immediately resumes.

Workaround

• Right‑click inside the console (or press Esc) to clear any selection and unpause the process.
• To avoid accidental pauses, you can disable QuickEdit:

  1. Right‑click the console title bar → Properties → Options  
  2. Uncheck “QuickEdit Mode” → OK
  
  

Proposal for Documentation

1. Add a note to the README or Windows setup guide explaining QuickEdit’s pause behavior.
2. Recommend disabling QuickEdit or using modern terminal emulators (e.g., Windows Terminal, ConEmu) that don’t block on selection.
3. Link back to this discussion for detailed repro steps and context.