Cloudflare’s Gen X Servers Swap Intel for AMD EPYC
Cloudflare has historically built its servers around Intel processors and companion Intel components for networking and storage. With the rollout of its tenth-generation (Gen X) server platform, that changes: the new machines rely entirely on AMD silicon, marking the first time the company has deployed a server with no Intel parts at all.
The shift is part of a broader effort to balance performance against operational cost and power efficiency. Cloudflare previously evaluated ARM-based CPUs and continues to keep its software stack ARM-ready, but for the current generation, AMD’s EPYC line won out after extensive testing.
Why AMD EPYC Won the Workload Tests
Cloudflare runs a homogeneous fleet where every server is capable of handling any service. That architectural choice drove the selection process for the Gen X CPU: the company benchmarked key workloads including cryptography, compression, regular expressions, and LuaJIT, then simulated typical production traffic patterns and measured requests per watt.
Based on those results, Cloudflare selected a single-socket 48-core AMD 2nd Gen EPYC 7642. In lab testing, that single processor outperformed the previous Gen 9 server, which used dual Intel Xeon Platinum 6162 chips with the same total core count. The win came down to two factors: a large L3 cache that produced a low cache miss rate, and a higher sustained operating frequency.
Performance Gains and Gen X Tuning
The production benchmarks show measurable improvements over Gen 9. The Gen X server handles as much as 36% more requests while costing notably less to run. Cache behavior improved as well, with an L3 cache miss rate that is roughly 50% lower, and NGINX p99 latency dropped by up to 50%. The EPYC 7642 also runs with a TDP that is 25% lower per core than the prior Intel configuration.
Cloudflare worked directly with AMD to squeeze out additional performance from the EPYC 7642. By enabling power determinism and explicitly configuring the CPU’s TDP, the two companies achieved a further 6% gain over stock settings.
Memory Encryption Without the Performance Hit
The EPYC platform also brought a security benefit Cloudflare found attractive: Secure Memory Encryption (SME). Built into the AMD SoC architecture, SME encrypts system RAM and helps protect against data exfiltration if a physical server is stolen. Testing showed the feature could be enabled with no meaningful performance penalty, so the Gen X servers ship with it active.
The Gen X platform is now in production across Cloudflare’s global network, which serves over 26 million Internet properties. The company says it will continue evaluating new hardware and remains open to ARM-based servers when their requests-per-watt profile becomes compelling.
