XenSocket: A High-Throughput Interdomain Transport for VMs

This paper presents the design and implementation of XenSocket, a UNIX-domain-socket-like construct for high-throughput interdomain communication; i.e., VM-to-VM on the same system. The design of XenSocket replaces the Xen page-flipping mechanism with a static circular memory buffer shared between two domains, wherein information is written by one domain and read asynchronously by the other domain. XenSocket draws on best-practice work in this field and avoids incurring the overhead of multiple hypercalls and memory page table updates by aggregating what were previously multiple operations on multiple network packets into one or more large operations on the shared buffer. While the reference implementation (and name) of XenSocket is written against the Xen virtual machine monitor, the principle behind XenSocket applies broadly across the field of virtual machines.