ModuleNotFoundError: import of xformers halted; None in sys.modules

[matthewc2003]

I am currently attempting to run the webui on a Debian 11 system, which works fine except for the error regarding No module 'xformers'. Proceeding without it . I have attempted multiple installations of xformers from here and here but to no avail.

I have identified that error message being thrown is in the repositories/stable-diffusion-stability-ai/ldm/modules/diffusionmodules/model.py inside the try/except block. Xformers/xformers.ops is able to be imported when inside the python interpreter but doesn't work in the script. I moved the import statements out of the try/except block and it returned this:

Traceback (most recent call last):
File "/home/stable-diffusion-webui/launch.py", line 307, in <module>
start()
File "/home/stable-diffusion-webui/launch.py", line 298, in start
import webui
File "/home/stable-diffusion-webui/webui.py", line 13, in <module>
from modules.call_queue import wrap_queued_call, queue_lock, wrap_gradio_gpu_call
File "/home/stable-diffusion-webui/modules/call_queue.py", line 7, in <module>
from modules import shared
File "/home/stable-diffusion-webui/modules/shared.py", line 17, in <module>
from modules import localization, sd_vae, extensions, script_loading, errors
File "/home/stable-diffusion-webui/modules/sd_vae.py", line 6, in <module>
from modules import shared, devices, script_callbacks, sd_models
File "/home/stable-diffusion-webui/modules/sd_models.py", line 18, in <module>
from modules.sd_hijack_inpainting import do_inpainting_hijack, should_hijack_inpainting
File "/home/stable-diffusion-webui/modules/sd_hijack_inpainting.py", line 7, in <module>
import ldm.models.diffusion.ddpm
File "/home/stable-diffusion-webui/repositories/stable-diffusion-stability-ai/ldm/models/diffusion/ddpm.py", line 26, in <module>
from ldm.models.autoencoder import IdentityFirstStage, AutoencoderKL
File "/home/stable-diffusion-webui/repositories/stable-diffusion-stability-ai/ldm/models/autoencoder.py", line 6, in <module>
from ldm.modules.diffusionmodules.model import Encoder, Decoder
File "/home/stable-diffusion-webui/repositories/stable-diffusion-stability-ai/ldm/modules/diffusionmodules/model.py", line 11, in <module>
import xformers
ModuleNotFoundError: import of xformers halted; None in sys.modules

Any help would be appreciated.
Currently running on python 3.10.7

[ataa]

You can find xformers official binaries here (ubuntu) or you can build it from source using:

# (Optional) Makes the build much faster
pip install ninja
# Set TORCH_CUDA_ARCH_LIST if running and building on different GPU types
pip install -v -U git+https://github.com/facebookresearch/xformers.git@main#egg=xformers
# (this can take dozens of minutes)

[matthewc2003]

I have already attempted to build from source, resulting in the error above. On another note, I noticed the torch version installed is 1.12.1+cu113, but my system is running CUDA 11.7. Could this be related?

[ouyangde]

just add command line args: --xformers
See the ugly codes:

cat modules/import_hook.py

import sys

this will break any attempt to import xformers which will prevent stability diffusion repo from trying to use it

if "--xformers" not in "".join(sys.argv):
sys.modules["xformers"] = None

Why not leave a log here?

[designerexpert]

Thank you for pointing this out!
I modified my webui-user.bat to add the command line arguments and it worked well for me :)
Contents of my webui-user.bat which may be useful for windows users having this issue.

@echo off

set PYTHON=
set GIT=
set VENV_DIR=
set COMMANDLINE_ARGS="--xformers"

call webui.bat

[uisato]

Worked!

[nayan-dhabarde]

Worked!

[DJMaxIIDX]

Worked！！！THX！！！

[liuzimo]

if "--xformers" not in "".join(sys.argv):
import xformers
sys.modules["xformers"] = xformers
print(sys.argv,sys.modules["xformers"])

[joeyskyist]

it is useful

[sanromd]

This allowed me to load xformers. Thank you, @liuzimo