Скачать или смотреть [2020] HA-IOV: Applying Hardware-assisted Techniques to IO Virtualization Framework

In I/O virtualization, notification mechanism, such as ioeventfd, achieves a significant fraction of request latency as long as I/O physical devices become faster. Polling techniques can reduce latency but prevents other threads from running and waste CPU if events are rare. This talk introduces HA-IOV, an efficient and flexible hardware-assisted I/O Virtualization framework, to obtain high CPU utilization as well as satisfying performance. First, VMs can deliver I/O requests to asynchronous I/O processing threads without trapping out by hardware support to reduce delivery latency. I/O processing threads are further wakened up by hardware-assisted scheduler with no kernel scheduler overheads. Polling mode can thus be eliminated in HA-IOV to improve CPU utilization. Second, HA-IOV allows VMs to trap out to user-level threads bypassing KVM, leading to a reduction of synchronous I/O path.

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Yifei Jiang
Huawei, Chief Engineer

Yifei Jiang is a chief engineer at Huawei, and has 9 years working experience on Virtualization. Currently working on next generation virtualization technology research.

Bo Wan
Huawei, Senior engineer

Bo Wan, Doctor of University of Science and Technology of China, is a senior engineer in Huawei. He is working on the ongoing next generation virtualization project.