Accelerating Two-Dimensional PageWalks for Virtualized Systems
Nested paging is a hardware solution for alleviating the software memory management overhead imposed by system virtualization. Nested paging complements existing page walk hardware to form a Two-Dimensional (2D) page walk, which reduces the need for hypervisor intervention in guest page table management. However, the extra dimension also increases the maximum number of architecturally-required page table references. This paper presents an in-depth examination of the 2D page table walk overhead and options for decreasing it. These options include using the AMD Opteron processor's page walk cache to exploit the strong reuse of page entry references.