This might be useful in a case where a small lookup or similar is often pushed out from cache such that lookups are usually cold. Yet lookup data might by small enough to not cause issue with cache pollution, increased bandwidth or memory consumption.
In this case it’s better to asynchronously bring the data into the cache, which you can do with a prefetch shortly before the read.
Perhaps. Then again, if your target is to reduce dram refresh induced latency, you might not have time to prefetch either.