=== ComfyUI RealVisXL no-mmap Stable Baseline ===
Date: 2026-06-20

--- Previous baseline ---
Tag: rocm-sd15-working-baseline (preserved, not modified)

--- This baseline adds ---
Fix:   comfy/utils.py: _load_safetensors_no_mmap() for files >4 GB
Model: RealVisXL_V4.0.safetensors (6.46 GB) - path only, not in git
Test:  768x1024, 25 steps, cfg=6, dpmpp_2m, karras -> OK

--- Root cause of crash (diagnosed & fixed) ---
Strix Halo UMA: ROCm init reserves ~14 GB GPU virtual address space.
safetensors mmap of files >~4 GB then fails (Windows VA space exhausted).
SD1.5 (3.97 GB) < threshold -> mmap OK.
SDXL fp16 (~6.5 GB) > threshold -> access violation in safe_open().
Fix: sequential file-read (open+seek+read) bypasses mmap entirely.

--- Patch location ---
File:      comfy/utils.py
Functions: _load_safetensors_no_mmap(), _LARGE_FILE_MMAP_THRESHOLD = 4_000_000_000
Branch:    load_torch_file() elif os.path.getsize > threshold and cuda available

--- Startup command ---
cd %USERPROFILE%\ComfyUI
.\venv\Scripts\activate
python main.py --disable-dynamic-vram --disable-mmap

--- GPU / ROCm ---
torch:    2.7.0a0+git3f903c3
Device:   AMD Radeon(TM) 8050S Graphics
VRAM GB:  14.37
ROCm:     6.5 / gfx1151 (Strix Halo)

--- Models in checkpoints (not in git) ---
v1-5-pruned-emaonly.safetensors   3.97 GB  SD1.5 baseline
RealVisXL_V4.0.safetensors        6.46 GB  SDXL realistic portrait

--- Working parameters (RealVisXL) ---
Resolution:   768x1024
Steps:        25
CFG:          6
Sampler:      dpmpp_2m
Scheduler:    karras
Batch size:   1

--- Recovery commands ---
# 1. Return to this code state:
git checkout rocm-realvisxl-nommap-working

# 2. Re-download RealVisXL if needed (not in git):
# python -c "from huggingface_hub import hf_hub_download; hf_hub_download(repo_id='SG161222/RealVisXL_V4.0', filename='RealVisXL_V4.0.safetensors', local_dir='models/checkpoints')"

# 3. Start ComfyUI:
# python main.py --disable-dynamic-vram --disable-mmap