As far as I understand, since user most likely voted only on a small subset of those 100 comments (say 3) and negative lookups are very fast because of bloom fi

As far as I understand, since user most likely voted only on a small subset of those 100 comments (say 3) and negative lookups are very fast because of bloom filters [1], therefore all lookups combined are fast. [1] https://en.wikipedia.org/wiki/Bloom_filter https://en.wikipedia.org/wiki/Bloom_filter