On Sun, Dec 16, 2018 at 09:09:48AM +0800, Qixuan Wu wrote:
1) Did you compare the performance to the virtio-blk raw or qcow2 solution of normal virtual machine?
Not yet. Guest and host page cache performance can dominate benchmarks, so we typically use fio direct=1 with QEMU -drive cache=none (O_DIRECT) to focus purely on disk I/O performance and not page cache. The same thing can be done with virtio-fs so that every I/O operation requires communication with the host. In theory virtio-fs should be comparable to virtio-blk on raw. In real-world scenarios the page cache will be enabled, especially for the virtio-fs DAX feature. So I need to think carefully about what to benchmark, but it will probably include both configurations.
2) Whether does it impact live-migration of guest os ?
Virtio-fs currently does not support live migration. Is there a requirement for live migration with Kata Containers use cases? Stefan