Python Out of Memory in ComfyUI

Telemetry snapshot queried on April 17, 2026: 20 events across 8 installs for comfyui_fatal_error_detected.

What telemetry shows

• These incidents point to system RAM or CPU-side allocation failures rather than GPU VRAM exhaustion.
• Sample telemetry lines included MemoryError and DefaultCPUAllocator: not enough memory.

What users usually notice

• Workflows fail mid-run even when GPU memory does not look maxed out.
• The machine becomes sluggish or heavily paged before the failure.

What to do next

1. Lower resolution, frame count, batch size, or workflow parallelism.
2. Close RAM-heavy background apps and increase page file limits if needed.
3. Split large workflows into smaller stages and persist intermediate outputs.

Escalate when

• Medium-size workflows fail on machines that should have enough RAM.
• A launcher update causes the same workflow to use much more memory than before.