Inside Gen 13- how we built our most powerful server yet
Mar 23, 2026Syona Sarma, JQ Lau, Ma Xiong, Victor Hwang
Summary
This post details the engineering rationale behind the selection of components for Cloudflare's Gen 13 server hardware. It covers the evaluation and choice of the AMD EPYC™ 9965 Turin processor, highlighting the trade-off of L3 cache for increased core count due to the FL2 software stack's reduced cache dependency. It also details the memory configuration (12x 64GB DDR5-6400 ECC RDIMMs) for optimal bandwidth and capacity, the move to PCIe 5.0 NVMe drives for increased storage capacity and bandwidth, and the adoption of dual 100 GbE network interface cards. The post also discusses the rationale for selecting the 9965 processor based on performance per watt, TCO, operational simplicity, and forward compatibility.
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