Motif 2.6B tech report is pretty insane, first time i see a model with differential attention and polynorm trained at scale!
> It's trained on 2.5T of token, with a "data mixture schedule" to continuously adjust the mixture over training. > They use WSD with a "Simple moving average" averaging the last 6 ckpt every 8B token. > They trained on Finemath, Fineweb2, DCLM, TxT360. > Lot of details in the finetuning data they used, for instance they used EvolKit and did some "dataset fusion" to have more compressed knowledge into the data. > They mention they also tried Normalized GPT, QK-Norm and Cross Layer Attention.
Kimi K2 tech report is full of gems as always. Here are my notes on it:
> MuonClip: Pretty crazy how after 70k the training stabilizes and the QK-clip is basically inactive. There is also no loss in perf with QK-clip which is not trivial at all (at small scale but with aggressive threshold). Also a cool explanation of why muon makes the logit explode in appendix E (tl;dr is that muon makes the singular value of the update matrix higher) > Sparsity scaling laws to justify their ratio, they have a very solid training infra that allows the model to be trained at this sparsity level, they could have increased even more but as sparsity increases the training becomes less efficient. > They diminish the number of attention heads to make it more efficient for long context since attention heads are a big bottleneck for long context. They also remove 2 of the 3 "first dense" layers in the dsv3 arch.
With the sparsity and attention heads (divided by 2) they achieve 83% increased flops compared to deepseek v3 arch at 128k.
> Data: Rephrasing is KEY. They do a lot more synthetic data generation and rephrase their corpus to have different styles, for longer documents they do it by chunk. I'm (half) surprised by the fact that ONLY 1 epoch (assuming same number of training tokens I think?) of data rephrased 10 times has better accuracy than 10 epochs of the same data rephrased once. > They do rewriting for Math and Knowledge, for Math they apply the ShallowMath recipe and instruct the model to rephrase in a "learning note" style > They talk about diversity and probably have some internal stuff/eval to test that, as always still a bit unclear for me how to properly measure that.
The infra is also very nice, quick summary: > PP=16 (1F1B schedule, a bit custom), EP=16, zero1 > No FP8 computation but for storage of specific layers, selective recomputation for inexpensive block, activation offloading to CPU
YAML engineering becomes more and more important than ever from infra provisioning to model training (recipes).
Here, I built a simple editor first for @dstackai, and I will share the live endpoint this week. Let me know what you think about this approach.
Based on this approach, if people think this is useful, I am going to do the same thing for the LLM training recipes for popular frameworks such as Hugging Face open-r1, Axolotl, and so on. Let me hear.
Google just dropped an exciting technical report for the brand-new Gemma3 model! 🚀 Here are my personal notes highlighting the most intriguing architectural innovations, design choices, and insights from this release:
1) Architecture choices: > No more softcaping, replace by QK-Norm > Both Pre AND Post Norm > Wider MLP than Qwen2.5, ~ same depth > SWA with 5:1 and 1024 (very small and cool ablation on the paper!) > No MLA to save KV cache, SWA do the job!
2) Long context > Only increase the rope in the global layer (to 1M) > Confirmation that it's harder to do long context for smol models, no 128k for the 1B > Pretrained with 32k context? seems very high > No yarn nor llama3 like rope extension
3) Distillation > Only keep te first 256 logits for the teacher > Ablation on the teacher gap (tl;dr you need some "patience" to see that using a small teacher is better) > On policy distillation yeahh (by @agarwl_ et al), not sure if the teacher gap behave the same here, curious if someone have more info?
4) Others > Checkpoint with QAT, that's very cool > RL using improve version of BOND, WARM/WARP good excuse to look at @ramealexandre papers > Only use Zero3, no TP/PP if i understand correctly ? > Training budget relatively similar than gemma2