Kan Wu

Hardware and OS mechanisms for memory tiering are widely deployed, yet datacenters still overprovision DRAM. The root cause is _hotness fragmentation_: allocators place objects by size rather than access pattern, so hot and cold objects become interleaved within the same pages. A single hot objec...

The traditional memory management problem maximizes application performance when constrained by a fixed-size memory. Today’s data centers face a different problem: their goal is to maximize the number of jobs on a server without violating performance Service Level Objectives (SLOs). Since a key c...

We present Mirror-Optimized Storage Tiering (MOST), a novel tiering-based approach optimized for modern storage hierarchies. The key idea of MOST is to combine the load-balancing advantages of mirroring with the space-efficiency advantages of tiering. Specifically, MOST dynamically mirrors a smal...