My bad. I was under the impression that most search engines are compute bound, but if anything there’s probably a glut of compute for such applications and a market appetite for better results.
Certainly caching is important, especially for Word2Vec or other NLP which you'd want to happen in a separate stage after crawl, but as someone mentioned in a sibling comment, there are some factors that are calculated per-query, which can have a lot of cache misses for novel queries.
