[NovaX]

What about MRU-biased workloads? For example an analytical loop or row scanning in a db query? In those cases recency is a negative signal and there may not be much frequency to extract (e.g. equal frequencies in a loop). Instead the policy has to avoid admissions to obtain some hits rather than be flushed for zero hits.

[heisjustsosmart]

Think you mean round robin, yes, that's an issue but that's equal probability, not high probability (his phrase). I don't know a scheduler that will handle that as well as handling LRU replacement well and if you have any cites I would appreciate them.

Also remember that many DBs are multi-user so any access patterns from each connection will get thrown in the same bucket.

[NovaX]

It is handled by W-TinyLFU where I use this scenario as a stress test [1]. While LIRS / LIRS2 did not pass this one scenario, the quality of the work behind that policy leads me to believe it could be improved to handle that case.

[1] https://github.com/ben-manes/caffeine/wiki/Efficiency#adapti...