Right now we locally cache within a single page load any db hits, but we do 1 db hit per name found. We could batch them up, dedup them, then do a single db hit. This would likely be a performance win.
We would need T323438: Benchmarks benchmarks before knowing if this is really a real concern however, and to know if this technique would help.
Imported from https://github.com/ofbeaton/mediawiki-realnames/issues/6