Hi Rob & Mihai, I wrote vhost-nvme patches on top of Christoph's NVMe target. vhost-nvme still uses mmio. So the guest OS can run unmodified NVMe driver. But the tests I have done didn't show competitive performance compared to virtio-blk/virtio-scsi. The bottleneck is in mmio. Your nvme vendor extension patches reduces greatly the number of MMIO writes. So I'd like to push it upstream. I port these 2 patches to newer kernel and qemu. I use ram disk as backend to compare performance. qemu-nvme: 29MB/s qemu-nvme+google-ext: 100MB/s virtio-blk: 174MB/s virtio-scsi: 118MB/s I'll show you qemu-vhost-nvme+google-ext number later. root@guest:~# cat test.job [global] bs=4k ioengine=libaio iodepth=64 direct=1 runtime=120 time_based rw=randread norandommap group_reporting gtod_reduce=1 numjobs=2 [job1] filename=/dev/nvme0n1 #filename=/dev/vdb #filename=/dev/sda rw=read Patches also available at: kernel: https://git.kernel.org/cgit/linux/kernel/git/mlin/linux.git/log/?h=nvme-google-ext qemu: http://www.minggr.net/cgit/cgit.cgi/qemu/log/?h=nvme-google-ext Thanks, Ming _______________________________________________ Virtualization mailing list Virtualization@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/virtualization
