Exo Labs claims 4.8 TB/s from four clustered M5 Ultra Mac Studios, and r/LocalLLaMA immediately called it aggregate-bandwidth marketing

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Exo announced it is now featured on Apple's M5 Ultra Mac Studio and M6/M5 Pro Mac mini product pages after a year of joint work on low-latency RDMA over Thunderbolt 5, saying aggregate memory bandwidth scales roughly linearly and that clusters run Kimi K3 and GLM-5.3 at API speeds. The r/LocalLLaMA thread (150 upvotes) is the useful part: the top technical reply (46 upvotes) points out you would report 4.8 TB/s even if the machines were connected by 90s modems across four continents, because it is just the sum of each machine's memory channels and RDMA has zero effect on that number. Others note Exo has not shipped a release in four months.