Optimizing network I/O virtualization through guest-driven scheduler bypass
Cox, Alan L.
Master of Science
Virtualization is increasingly utilized for consolidating server resources to improve efficiency by conserving power and space. However, significant hurdles remain in achieving satisfactory performance in a virtualized system. Notably, virtualization of network I/O continues to be a performance barrier. The driver domain model of I/O virtualization suffers from an inherent network performance disadvantage due to the necessity of scheduling a driver domain. However, this virtualization model is desirable because of its fault tolerance and isolation properties. In this work, I argue that it is possible to overcome the barrier of network I/O performance while maintaining domain protection by providing a i mechanism which enables guests to operate the driver domain on their own behalf without the intervention of the scheduler. I describe my implementation of the worldswitch mechanism and evaluate its performance. I show that with the worldswitch enabled, guests achieve higher bandwidth and lower latency than in an unmodified system.
Computer science; Applied sciences