aiqbench analysis
As large language models hit the data-bound regime, this research demonstrates that standard repetition fails to fully utilize existing organic text corpora. The proposed SynPro framework uses reinforcement learning to rephrase and reformat limited human data into diverse forms, effectively unlocking 3.4–5.2x more training tokens without introducing external information or causing distribution collapse. This approach offers a critical pathway for sustaining scaling laws when high-quality human-generated text becomes scarce.
Generating Pretraining Tokens from Organic Data for Data-Bound Scaling
arXiv:2605.17849v2 Announce Type: replace-cross Abstract: LLM pretraining is shifting from a compute-bound to a data-bound regime, where available human (organic) text falls far short of scaling demands. However, reaching the data-bound regime does not mean the model has fully utilized its organic corpus. In this paper, we introduce SynPro, a synthetic data generation framework that helps LLMs more thoroughly learn from limited organic data. SynPro applies two operations, rephrasing and reformatting, that present the same organic source in diverse forms to facilitate deeper learning without introducing external information. Both generators are optimized via reinforcement learning with quality, faithfulness, and data influence rewards, and are continuously updated as pretraining plateaus to target content the model has yet to absorb. We pretrain 400M, 1.1B, and 2B models with 10% of their Chinchilla-optimal tokens (0.8B, 2.2B, and 4B) from DCLM-Baseline, reflecting a realistic data-bound regime in frontier pretraining. Our results reveal that organic data is significantly underutilized by standard repetition: SynPro unlocks 3.4--5.2x the effective tokens of repetition, even surpassing the non-data-bound oracle that trains on equivalent unique data at the 1.1B and 2B scales. Analyses confirm that faithful, model-aware synthesis sustains data-bound scaling without causing distribution collapse. We open-source our code at https://github.com/cxcscmu/SynPro.
Abstract:LLM pretraining is shifting from a compute-bound to a data-bound regime, where available human (organic) text falls far short of scaling demands. However, reaching the data-bound regime does not mean the model has fully utilized its organic corpus. In this paper, we introduce SynPro, a synthetic data generation framework that helps LLMs more thoroughly learn from limited organic data. SynPro applies two operations, rephrasing and reformatting, that present the same organic source in diverse forms to facilitate deeper learning without introducing external information. Both generators are optimized via reinforcement learning with quality, faithfulness, and data influence rewards, and are continuously updated as pretraining plateaus to target content the model has yet to absorb. We pretrain 400M, 1.1B, and 2B models with 10% of their Chinchilla-optimal tokens (0.8B, 2.2B, and 4B) from DCLM-Baseline, reflecting a realistic data-bound regime in frontier pretraining. Our results reveal that organic data is significantly underutilized by standard repetition: SynPro unlocks 3.4--5.2x the effective tokens of repetition, even surpassing the non-data-bound oracle that trains on equivalent unique data at the 1.1B and 2B scales. Analyses confirm that faithful, model-aware synthesis sustains data-bound scaling without causing distribution collapse. We open-source our code at this https URL.
Computation and Language (cs.CL); Artificial Intelligence (cs.AI); Machine Learning (cs.LG)
arXiv:2605.17849 [cs.CL]
(or arXiv:2605.17849v2 [cs.CL] for this version)
https://doi.org/10.48550/arXiv.2605.17849 Focus to learn more arXiv-issued DOI via DataCite
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