Skip to main content
PreprintsShort CommunicationNot peer reviewedVersion 1 Open access

Speculative Decoding Under Memory Constraints

  1. 1 Meridian University, Pune, India
  2. 2 Kestrel AI Institute, Tokyo, Japan

First posted 5 November 2026

DOI 10.xxxx/ctm.pp.2026.0009 · ID CTM-PP-2026-0009

Cite this record

Desai, R. & Saito, Y. (2026). Speculative Decoding Under Memory Constraints [Preprint, version 1]. CONTINUUM Preprints. doi:10.xxxx/ctm.pp.2026.0009
Request peer review

This preprint has not been peer reviewed. It was screened for scope and compliance only. Its authors can request open peer review at any time.

Sample record. This work is fictional demonstration content. Results, people and institutions are placeholders; references in full-text articles are real publications.

Highlights

  • A draft that shares embeddings and lower layers with the target model.
  • Extra memory falls from 11% to 3%; 88% of the speed-up is retained.

Abstract

Speculative decoding accelerates generation by letting a small draft model propose tokens that a larger model verifies, but the draft model competes with the target model for scarce memory on edge devices. We characterise the trade-off between draft-model size, speed-up and memory footprint, and propose a draft that shares the target model's embedding table and lower layers. The shared draft reduces extra memory from 11% to 3% of the target model and retains 88% of the speed-up of an independent draft.

Keywords speculative decoding · edge inference · memory · language models

1.Introduction

Autoregressive decoding is bound by memory bandwidth. Speculative decoding [1] uses a draft model to propose several tokens at once, so that the target model can verify them in one pass. On servers the draft model's memory is negligible; on a phone it is not.

2.Results

Figure 1 shows the speed-up against additional memory for independent drafts of increasing size and for the shared-layer draft. The shared draft lies on a better frontier: at 3% additional memory it achieves a 1.9× speed-up, against 1.4× for an independent draft of equal memory.

11.21.41.61.822.22471116Additional memory (%)Speed-up (×)
  • Independent draft
  • Shared-layer draft (ours)
Figure 1. Decoding speed-up (×) against additional memory (% of target model). Synthetic placeholder data.

Declarations

Author contributions
R.D. designed the method; Y.S. carried out the device measurements.
Funding
Sample article – no funding to declare.
Competing interests
The authors declare no competing interests.
Data and code availability
Sample article. All results, names and affiliations in this demonstration article are synthetic placeholders.

References

  1. [1]Leviathan, Y., Kalman, M., Matias, Y. (2023). Fast inference from transformers via speculative decoding. Proceedings of the 40th International Conference on Machine Learning, 202, 19274–19286. arXiv:2211.17192
  2. [2]Vaswani, A., Shazeer, N., Parmar, N., Uszkoreit, J., Jones, L., Gomez, A. N., Kaiser, Ł., Polosukhin, I. (2017). Attention is all you need. Advances in Neural Information Processing Systems, 30. arXiv:1706.03762

Versions

  1. Version 1 · 5 November 2026Latest

    First version.

    10.xxxx/ctm.pp.2026.0009.v1

How to cite

Desai, R. & Saito, Y. (2026). Speculative Decoding Under Memory Constraints [Preprint, version 1]. CONTINUUM Preprints. doi:10.xxxx/ctm.pp.2026.0009

Cite this record

Desai, R. & Saito, Y. (2026). Speculative Decoding Under Memory Constraints [Preprint, version 1]. CONTINUUM Preprints. doi:10.xxxx/ctm.pp.2026.0009

© 2026 The authors. Published by AEX CONTINUUM under the CC BY 4.0 licence.