Automatic Sage Attention Breaks Other ComfyUI Models

[davidledo]

Hello,

I noticed that in this node as well as a few others like the Sam3D, SageAttention is automatically turned on in comfyUI even if I am not starting Comfy with the command line arguments "--use-sage-attention". I have no way of turning it off. This breaks a lot of models, especially image models like Qwen Image and ZImage. The only workaround I've found is to uninstall the node and update Comfy so it overrides the new setting.

Is there an easy fix? I'm currently investigating this myself.

Thanks for your time and help!

[davidledo]

Suggestion from Claude was to add this in line 6 of prestartup_script.py (so take this vibecode suggestion with a grain of salt):

from comfy.cli_args import args
if "--use-sage-attention" not in sys.argv:
    args.use_sage_attention = False
if "--use-flash-attention" not in sys.argv:
    args.use_flash_attention = False

I got it to work but I have to always set the attn_backend to sage. I do notice a subtle dip in quality of renders, though.

[PozzettiAndrea]

@davidledo Hi! Apologies for this 🙏 this was a totally unnecessary and disastrous decision on my end, which has since been reverted. Please do let me know if you have any more issues in the future and apologies again. The latest version (0.2.16) should be very far removed from this and still one click installable.