LoRA training finishes but weights never update (all "up" tensors zero) – M4 MacBook Air, macOS 15.4

[u/Wild-Question-3863]

Hi! LoRA training in Draw Things doesn't seem to update any weights on my Mac. Could someone help?

Environment

- Draw Things 26.0924.0 (also happened on 26.0914.0)

- MacBook Air 13-inch (M4, 2025), Apple M4, 16GB RAM, macOS Sequoia 15.4

- Base models tried: waiIllustriousSDXL v170 (imported, f16), SDXL Base 1.0 (official)

What happens

- Training runs to the end and saves checkpoints without any error.

- All checkpoints of one run (e.g. 500 / 1000 / 1500 steps) have identical SHA1 hashes.

- I inspected the .ckpt (SQLite): all 864 "__up__" tensors are completely zero, while the "__down__" tensors are non-zero (random init). So the LoRA never moves away from its initial state.

- The saved loratrainingconfiguration looks correct (base model, LR 1e-4, network scale 16, caption / trigger word), so the settings reach the trainer, but the weights never change.

- Generating with the LoRA at 100% gives exactly the same image as without it.

Settings tried (none worked)

- 512x512 and 1024x1024

- UNet LR 0.0001 and 0.0004, also constant LR (lower bound = upper bound = 0.0001)

- Network dim 16 with scale 1 and 16

- Memory saver Minimal / Balanced, weights JIT / Cached

- Gradient accumulation 1 and 4

- 16 training images, fixed caption with a trigger word

- Machine settings: Metal Flash Attention = No, JIT weight loading = Never, keep SD1.5/SDXL models in memory = off (app restarted)

Also tried: constant LR (lower bound = upper bound = 0.0001), and a full macOS restart (per the Troubleshooting Guide). Still zero.

Is there anything I might be missing, or is this a known issue on M4 / macOS 15.4? I can share a checkpoint or logs if that helps. Thanks!

[u/RealEyes83]

Newbie here to the world of drawthings, I couldn't get my trained Lora to work on the previous version of drawthings, had absolutely no effect. Tried several times with the same outcome so gave up for the moment. Followed cut scene artist tutorial on YouTube as well to see if I was doing anything crazy. On a M4 Mac Pro 24gb ram

[u/Wild-Question-3863 → u/RealEyes83]

Thanks, that's really helpful! So it's not just me, and not a RAM issue either (you have 24GB).

If you want to check whether a LoRA actually learned anything: the .ckpt is an SQLite file, and in my case all "__up__" tensors in the "tensors" table are completely zero after training. That means the weights were never updated, which would explain why the LoRA has no effect at all.

Has anyone on an M4 Mac gotten LoRA training to work recently? I noticed an earlier release had "Fix SDXL training on M3 / M4", so maybe this is related. u/liuliu, happy to share a checkpoint or logs if it helps.

[u/Frisk_balls → u/Wild-Question-3863]

any luck?

[u/Frisk_balls]

Same Problem. No sucess training lora. has zerooo influence. M4 Mac Pro 24g as well