Skip to content
aiqbench takeMachine Learning

aiqbench analysis

This study investigates greedy block-wise local learning for large language model pretraining, revealing how gradient isolation impacts performance gaps across different model scales and block configurations. The research demonstrates that replacing MLP auxiliary layers with Transformer-based ones significantly recovers lost accuracy, while strategic application of multi-token prediction objectives optimizes the trade-off between parallel speedup and predictive pressure. These findings offer a practical roadmap for deploying decentralized training strategies without compromising the core capabilities required for autoregressive generation.
Sources coveringarXiv, LessWrong
What this isA model's reading of the article and related coverage, written for aiqbench. Not the publisher's words.

Greedy Local Learning for Language Model Pretraining: Gaps and Objective Design

arXiv3 min read

arXiv:2610.04867v1 Announce Type: cross Abstract: Greedy block-wise local learning splits a network into gradient-isolated blocks trained by local auxiliary losses, deleting the backward pass between blocks: inter-stage communication becomes forward-only and every block can step its optimizer independently, properties directly relevant to decentralized model-parallel training. Local learning is competitive with end-to-end backpropagation on image classification, and on small Transformers it is known to trade a worse best loss for parallel speedup. How this loss gap behaves in autoregressive language model (LM) pretraining at larger scale, and which auxiliary designs reduce it, has not been measured. We present a token-budget-matched empirical study at 125M and 400M parameters with $K \in \{1,2,4\}$ blocks at Chinchilla-optimal budgets, factorizing the auxiliary design into network architecture and training objective. We observe: (i) the gap to end-to-end training more than doubles from $K=2$ to $K=4$, but at $K=4$ shrinks from 125M to 400M; (ii) replacing an MLP auxiliary with a Transformer-based one is a strong network-side intervention, recovering 22-41% of the gap; (iii) a multi-token-prediction (MTP) auxiliary objective helps at the first block boundary, whereas adding it at deeper boundaries hurts, and restricting it to the first block yields the best $K=4$ configuration ($+0.062$ vs. $+0.075$ nats at 400M); and (iv) deployment-style per-block execution reduces activation memory by up to $2.2\times$. We frame these results as an empirically grounded method direction rather than a finalized method: local objectives should apply future-predictive pressure selectively across boundaries while resisting shortcuts that bypass predictive content.

Abstract:Greedy block-wise local learning splits a network into gradient-isolated blocks trained by local auxiliary losses, deleting the backward pass between blocks: inter-stage communication becomes forward-only and every block can step its optimizer independently, properties directly relevant to decentralized model-parallel training. Local learning is competitive with end-to-end backpropagation on image classification, and on small Transformers it is known to trade a worse best loss for parallel speedup. How this loss gap behaves in autoregressive language model (LM) pretraining at larger scale, and which auxiliary designs reduce it, has not been measured. We present a token-budget-matched empirical study at 125M and 400M parameters with $K \in \{1,2,4\}$ blocks at Chinchilla-optimal budgets, factorizing the auxiliary design into network architecture and training objective. We observe: (i) the gap to end-to-end training more than doubles from $K=2$ to $K=4$, but at $K=4$ shrinks from 125M to 400M; (ii) replacing an MLP auxiliary with a Transformer-based one is a strong network-side intervention, recovering 22-41% of the gap; (iii) a multi-token-prediction (MTP) auxiliary objective helps at the first block boundary, whereas adding it at deeper boundaries hurts, and restricting it to the first block yields the best $K=4$ configuration ($+0.062$ vs. $+0.075$ nats at 400M); and (iv) deployment-style per-block execution reduces activation memory by up to $2.2\times$. We frame these results as an empirically grounded method direction rather than a finalized method: local objectives should apply future-predictive pressure selectively across boundaries while resisting shortcuts that bypass predictive content.

Accepted at the NeurIPS 2026 Workshop on Collaborative, Open, and Decentralized Training of Foundation Models (CODEC-FM). 13 pages, 3 figures, 8 tables

Machine Learning (cs.LG); Artificial Intelligence (cs.AI)

arXiv:2610.04867 [cs.LG]

(or arXiv:2610.04867v1 [cs.LG] for this version)

https://doi.org/10.48550/arXiv.2610.04867 arXiv-issued DOI via DataCite (pending registration)

Full text under the publisher's open licence · 284 words

Related coverage