OS-level virtualization (e.g., Linux containers) has become a cornerstone of modern cloud systems. While it offers the illusion of isolated kernels for processes, these processes share the same underlying kernel, raising critical concerns around security, fault isolation, and the inability to customize kernels. Existing solutions address the issues by employing virtual machines that isolate kernels. However, these approaches incur significant performance overhead.

Memory tiering, which extends local DRAM by incorporating remote DRAM or NVM via Compute Express Link (CXL), offers a promising solution to the DRAM capacity scaling problem. However, in multi-tenant cloud environments, efficient management of fast memory requires not only optimizing data movement across tiers but also effectively distributing DRAM capacity when tenants compete. Moreover, bandwidth utilization is critically impacted by memory request rejection, which depends on the distribution of local DRAM. While previous research has extensively addressed data movement, DRAM distribution among multiple tenants remains underexplored.