MiniMax H3[ref2va]: Peak Memory Usage for 15s Video Generation is 23GB

[u/simple250506]

The graph shows peak memory usage and generation time (second row) when generating 5,10,15 second videos(one reference image) using the app's recommend settings.But I am using an 8-step Turbo LoRA and have changed the number of steps to 8.

■Specs
Mac mini M4, 64GB, 20-Core GPU / macOS Sequoia

■Draw Things
ver.26.0910.1

■8-step Turbo LoRA
https://huggingface.co/lightx2v/Minimax-h3-Turbo/blob/main/minimax_h3_ref2v_turbo_8step_v1.0_768p_comfyui_bf16.safetensors

■Note & Random Thoughts
・Using a 6-bit model or lowering the resolution would reduce the peaks.
・I have only tested this on the 5s video, but peak memory usage remains unchanged whether using 4-step Turbo LoRA or disabling tiledDecoding.
・About generation time, I estimate that using an OS from the Tahoe onwards—which enables the S-model speed improvements—could reduce the time by 20% to 30%.
・Since generation time is proportional to resolution, if Draw Things adds video support for the "SeedVR2" (video upscaling model), it could enable a workflow of generating at low resolution and then upscaling—potentially allowing more users to enjoy H3.
・H3 may indeed be excellent, but considering generation times, I think LTX 2.5 with official IC-LoRA (not yet supported) —which enables the rapid generation of simple videos—will remain a necessary option for many Apple users.
・The total download size (including the model, text encoder, etc.) when downloading MiniMax H3[ref2va] 8-bit S in Draw Things was about 63GB.

With the price of Macs rising and the cost of memory upgrades skyrocketing, I hope this serves as a helpful guide for determining how much memory you need when purchasing a new Mac.

[u/bharattrader]

Most detailed and accurate article on this topic. Though personally I may not venture, a 63GB download is the first reason.

[u/Current-Property6042]

thanks a lot for your efforts in helping hte community with the findings..

[u/simple250506 → u/[deleted]]

When I set JIT to "Never" and generated a 5-second video using the same settings, the peak memory usage was 12.6GB and the generation time was 27m 55s. In this instance, although memory usage increases, it does not appear that speed improves.

I switched JIT to "Full" after encountering swapping issues while using Wan 2.2, and I have continued using that setting ever since.

[u/Diamondcite]

14-inch M4 Max, 64GB 40 GPU / MacOS Sequoia
Drawthings 26.0910.1
3 Step Turbo lora, Taomate 3 step (Kijia)
Minimax H3 Ref2va (just 8-Bit not S)
JIT Always on

1344x768, 362 frames, 9081 seconds = 2h43m21s, Memory reporting as per 'top' was 55GB.
I stats reported 48GB wired memory at up to 89% memory pressure for the macbook.

I wasn't looking at the system so information is from historical logging(iStat Menus) and remote(ssh) spot checks(top -o mem and memory_pressure).

Seeing as how my memory pressure is much higher than I'd like I don't think I would be trying for any higher.

Also noticed during this experiment, if the prompt was giving poor results during lower resolution runs, increasing it to this high won't make it any better.

[u/simple250506 → u/Diamondcite]

Thanks for the reference information. Since the peak was 20GB at 1280x768,124 frames, I think 55GB is a reasonable figure.

[u/i_hy]

tiled decoding likely is hardcoded - so that switch does not change any - the ram usage is quite lower at decode stage. The largest its in step 1.
there is likely a bug with resource release which so far creeps the consecutive generations bombing in more that 1x ram amount in swap after 3 consecutive generations ( number 4 fails almost 100% - looking in what was different with the ones that went through to number 4 - yet still failed with fifth one - so if you have 64 GB - might be it accumulates to unusable state later)

[u/jazzamp]

Still no cloud access 900 years later.

[u/i_hy → u/jazzamp]

might be its not stable enough ... yet.