Multiplexed Rank DIMMs (MRDIMMs) have recently emerged as memory devices that enable higher bandwidth without increasing DRAM chip frequencies. This paper presents a detailed performance, power and energy evaluation of a production server with high-end MRDIMM main memory. The memory system upgrade from conventional registered DIMMs (RDIMMs) to MRDIMMs extends the bandwidth by 41% yielding 27-41% higher performance for bandwidth-bound workloads. Additionally, the latency improvement reaches hundreds of nanoseconds, benefiting a broad class of workloads sensitive to memory latency. At the same bandwidth utilization levels, RDIMMs and MRDIMMs exhibit similar power consumption. In the MRDIMM-extended bandwidth region, the performance improvements largely exceed the power increase, delivering up to 30% server energy savings for memory-bound workloads.
@article{arxiv.2605.02371,
title = {Performance and Energy Benefits of MRDIMMs},
author = {Pau Díaz and Mariana Carmin and Pouya Esmaili-Dokht and Victor Xirau and Felippe Zacarias and Henrique Potter and Harald Servat and Miquel Moreto and Eduard Ayguadé and Petar Radojković},
journal= {arXiv preprint arXiv:2605.02371},
year = {2026}
}