Home Made CobbleDB Replaces DynamoDB at Perplexity to Cut Query Latency 5x and Reduce Cloud Storage
Perplexity replaced DynamoDB in its high-volume search-serving path with CobbleDB, an internally built Rust key-value store, reporting fivefold lower batch-read latency and at least 20% lower storage costs.
The workload is unusual: each search fans out to roughly 100–120 page keys, with records averaging about 50 KB, at more than 200,000 requests per second. Perplexity split durable state, batch aggregation, and hot reads across YTsaurus/Pillar, Lorry, and CobbleDB. That separation keeps crawl and re-embedding writes from contending with live retrieval. The results and cost figures are Perplexity’s own; InfoQ has no article comment section for community reactions.