Dynamic page size selection for virtual memory sharing

Abstract

Techniques for managing the memory of computing devices that host multiple VMs by selecting optimally sized pages of virtual memory for programs running in the VMs. Virtual memory has traditionally been divided into pages of a single size (e.g., small, large, or huge) that are then offered to programs running in VMs. These page sizes have different benefits and drawbacks that must be considered when selecting the best page size for virtual memory. For example, small pages increase memory sharing between the VMs, but also result in an execution slowdown. Conversely, large pages improve execution performance by reducing latency in address translations, but limit memory sharing. This disclosure describes using small pages for sharable memory, and using large pages for private memory that cannot be shared. This provides the high performance needed for certain applications by using large pages, but still allows for increased memory sharing using small pages.