Logical Partitions on Many-Core Platforms

Abstract

Cloud platforms that use logical partitions to allocate dedicated resources to VMs can benefit from small and therefore secure hypervisors. Many-core platforms, with their abundant resources, are an attractive basis to create and deploy logical partitions on a large scale. However, many-core platforms are designed for efficient cross-core data sharing rather than isolation, which is a key requirement for logical partitions. Typically, logical partitions leverage hardware virtualization extensions that require complex CPU core enhancements. These extensions are not optimal for many-core platforms, where it is preferable to keep the cores as simple as possible. In this paper, we show that a simple address-space isolation mechanism, that can be implemented in the Network-on-Chip of the many-core processor, is sufficient to enable logical partitions. We implement the proposed change for the Intel Single-Chip Cloud Computer (SCC). We also design a cloud architecture that relies on a small and disengaged hypervisor for the security-enhanced Intel SCC. Our prototype hypervisor is 3.4K LOC which is comparable to the smallest hypervisors available today. Furthermore, virtual machines execute bare-metal avoiding runtime interaction with the hypervisor and virtualization overhead.