Combine multiple access bits with size-dependent retention credit

Develop a Sieve-based caching design that combines multiple access bits per object with size-dependent retention credit.

Background

The paper evaluates Sieve variants that assign retention credit according to object size and reports that allowing up to eight retention tokens can substantially improve object hit rate, especially for workloads with highly variable object sizes. It also notes related work on randomized SIEVE/CLOCK variants that use multiple access bits per object.

The unresolved problem is to integrate these two mechanisms: multiple access bits or equivalent multi-bit reuse state, together with size-dependent retention credit. The paper identifies this combination as future work rather than analyzing or evaluating it.