Perplexity Introduces Photon: A Rust-Based Retrieval Engine That Cuts p99 Latency From 800 ms to 65 ms

תקציר מקורי באנגליתPerplexity has released Photon , an in-house retrieval and ranking engine written in Rust. It replaces an open-source engine Perplexity had forked for its AI-native search stack. Photon now handles retrieval and ranking for all production traffic. It also powers a new Fast Search mode in the Perplexity Search API. Perplexity reports single-call latency of 160 ms at p50 and 230 ms at p95. Is it deployable? Yes, as a hosted API. Set search_type: "fast" on POST /search and pay $1 per 1,000 requests. Photon itself is not open source, so the engine cannot be self-hosted. Why Perplexity Replaced its Old Engine The old engine hit 3 limits as the index grew: Tail latency: Production p99 sat near 800 ms. The dataset exceeded RAM, so mlock was not an option. Cold reads triggered major page faults th