Optically connected memory for disaggregated data centers

Author(s)

Gonzalez, Jorge ; Palma, Mauricio G. ; Hattink, Maarten ; Rubio-Noriega, Ruth ; Orosa, Lois ; Mutlu, Onur ; Bergman, Keren ; Azevedo, Rodolfo

• Document type: Journal article
• Source: JOURNAL OF PARALLEL AND DISTRIBUTED COMPUTING; v. 163, p. 13-pg., 2022-02-22.

Abstract

Recent advances in integrated photonics enable the implementation of reconfigurable, high-bandwidth, and low energy-per-bit interconnects in next-generation data centers. We propose and evaluate an Optically Connected Memory (OCM) architecture that disaggregates the main memory from the computation nodes in data centers. OCM is based on micro-ring resonators (MRRs), and it does not require any modification to the DRAM memory modules. We calculate energy consumption from real photonic devices and integrate them into a system simulator to evaluate performance. Our results show that (1) OCM is capable of interconnecting four DDR4 memory channels to a computing node using two fibers with 1.02 pJ energy-per-bit consumption and (2) OCM performs up to 5.5 x faster than a disaggregated memory with 40G PCIe NIC connectors to computing nodes. (c) 2022 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 13/08293-7 - CCES - Center for Computational Engineering and Sciences
• Grantee: Munir Salomao Skaf
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 14/01642-9 - OMPSoC: Heterogeneous Optical Multiprocessor System on Chip Modeling
• Grantee: Jorge Luis Gonzalez Reano
• Support Opportunities: Scholarships in Brazil - Doctorate