Your vector index does not fit in RAM. Explain scalar and binary quantization with rescoring.
float32 is far more precision than ranking needs. int8 is close to free, binary is 32x smaller, and the difference between a working binary index and a recall disaster is one word: rescoring.
Updated Sep 2026 · Grounded in real GenAI, LLM, and AI/ML engineering interview loops and written to a senior-engineer editorial bar.
float32 is far more precision than ranking needs. int8 is close to free, binary is 32x smaller, and the difference between a working binary index and a recall disaster is one word: rescoring.
Lead with where the obvious approach breaks, because that is the judgment they are screening for — most candidates jump straight to the happy path and lose the room.
Then walk the failure back through the pipeline in order, naming the one metric the customer's exec sponsor actually cares about before you propose the fix.
