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OpenAI says its Habitat storage platform now serves 1 billion ChatGPT users across 40 regions, and read p50 fell from 120 ms to 10 ms

AspireAI community · OpenAI
OpenAI published the second part of its engineering write-up on Habitat, the storage platform behind ChatGPT, saying the system now serves over 500 petabytes of data for more than 1 billion users across 40 geographic regions, and that its largest Azure Cosmos DB account serves more than 20M queries per second. The team reports that rewriting a hot path in Rust and adding a global cache cut overall global read p50 from roughly 120 ms to roughly 10 ms, a 12x improvement since they started focusing on performance earlier this year. The post also documents the multi-tenancy design that came and went, the cost of capacity planning being pushed onto every product team, and the open trade-off between colocating storage with compute when datacenter power or cooling is scarce. The limitation is that most figures are OpenAI's own internal measurements and the write-up documents a platform readers cannot directly reproduce or benchmark.
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