More Cores, Less Cache - And It Still Got Faster | Cloudflare Gen 13
#ThisWeekinNET — Episode 134
In this episode of This Week in NET, JQ Lau and Victor Hwang from our Network & Infrastructure Strategy team walk us through Cloudflare's 13th generation of servers — the machines that power a significant part of the internet across 330+ cities worldwide.
The Gen 13 program doubled compute density by jumping from 96 to 192 cores, but that came with an 83% drop in L3 cache. The team explains how a bold hardware bet, combined with Cloudflare's FL2 Rust-based software rewrite, turned that trade-off into a win across throughput, latency, and power efficiency.
From counterintuitive fan physics to credit card pen tests on chassis intrusion switches, this conversation covers the full stack: CPUs, memory, storage, networking, security, and what's next — including post-quantum readiness at the hardware layer.
Check the Cloudflare Blog:
https://blog.cloudflare.com/gen13-launch/
https://blog.cloudflare.com/gen13-config/
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https://ThisWeekinNET.com
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Timestamps
00:53 — Blog recap: what Cloudflare announced (including agents can now actually create Cloudflare accounts, buy domains, and deploy)
02:40 — Meet JQ Lau and Victor Hwang
03:52 — From Gen 11 to Gen 13: the evolution of Cloudflare's servers
05:04 — Doubling compute power while cutting cache by 83%
06:54 — The journey to choosing the right CPU
10:04 — Scratchpad vs bookshelf: cache and memory explained
12:08 — Why 192 cores won over 128 cores
15:35 — FL2: Cloudflare's Rust-based software rewrite
18:12 — Hardware and software co-design: why neither works alone
18:37 — Memory, storage, and networking upgrades
22:18 — Dual GPU support and future accelerators
23:25 — Inside the Gen 13 chassis: what changed visually
24:51 — Why adding a 5th fan saves power (counterintuitive physics)
25:59 — Server security: memory encryption, PCIe encryption, intrusion detection
30:12 — 50% better performance per watt and what that means at scale
33:54 — The Austin lab: where hardware gets tested before production
35:10 — How AI helped design Gen 13
37:13 — 500 terabits per second: Cloudflare's network milestone
38:30 — What's next: Gen 14, rack-scale design, and post-quantum hardware
41:16 — Supply chain planning: lessons from COVID and the AI buildout