Z.ai's GLM-5.3 Essay: Scaling Law Has More Dials Than Parameter Count

pmttyji · reddit · 2026-08-19

Z.ai published a long essay on scaling laws, framed around GLM-5.3 as a controlled experiment: same base, architecture, and total/activated parameters as GLM-5.2, with only one month of scaled long-horizon environments and RL — yielding non-marginal gains.

The essay traces the field's evolution: Kaplan et al. (2020) fit parameters growing 2.7:1 over data, driving GPT-3, Gopher, MT-NLG; Hoffmann et al. (2022) (Chinchilla) redid it across 400 models, finding 20 tokens per parameter optimal and co-growth at scale — making the trillion-parameter round a field-wide detour.

Later shifts: with inference dominating lifetime cost, optima moved to smaller, deliberately over-trained models (Llama-2-7B, Gemma-2-9B at 290 and 889 TPP); under MoE, total parameters govern knowledge while activated parameters and depth govern reasoning chains; Roberts et al. (2025) find optimal TPP is task-dependent — memorization favors parameters, reasoning favors data, and pushing total parameters at fixed TPP degrades reasoning.

Conclusion: beyond a threshold, capability comes from effective depth and post-training. Base size, pretraining data, and per-forward-pass compute remain open; next up may be mid-training or pre-training.

Related event: Zhipu's Tang Jie Rethinks Scaling Law Beyond Parameter Count(2 posts)→

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