Christian, The test case for this is to:
- passthrough the NVMe disk to guest; - and run fio benchmarks against the passed-through NVMe disk in the guest. I have detailed these steps and pasted the commands in the bug description. Please let me know if steps are not clear. The only required HW is an NVMe disk. We (IBM) can verify and do the tests, if needed. Thank you! Murilo -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1847948 Title: Improve NVMe guest performance on Bionic QEMU Status in The Ubuntu-power-systems project: Triaged Status in linux package in Ubuntu: Fix Released Status in qemu package in Ubuntu: Fix Released Status in linux source package in Bionic: New Status in qemu source package in Bionic: Triaged Bug description: == Comment: #0 - Murilo Opsfelder Araujo - 2019-10-11 14:16:14 == ---Problem Description--- Back-port the following patches to Bionic QEMU to improve NVMe guest performance by more than 200%: ?vfio-pci: Allow mmap of MSIX BAR? https://git.qemu.org/?p=qemu.git;a=commit;h=ae0215b2bb56a9d5321a185dde133bfdd306a4c0 ?ppc/spapr, vfio: Turn off MSIX emulation for VFIO devices? https://git.qemu.org/?p=qemu.git;a=commit;h=fcad0d2121976df4b422b4007a5eb7fcaac01134 ---uname output--- na ---Additional Hardware Info--- 0030:01:00.0 Non-Volatile memory controller: Samsung Electronics Co Ltd NVMe SSD Controller 172Xa/172Xb (rev 01) Machine Type = AC922 ---Debugger--- A debugger is not configured ---Steps to Reproduce--- Install or setup a guest image and boot it. Once guest is running, passthrough the NVMe disk to the guest using the XML: host$ cat nvme-disk.xml <hostdev mode='subsystem' type='pci' managed='no'> <driver name='vfio'/> <source> <address domain='0x0030' bus='0x01' slot='0x00' function='0x0'/> </source> </hostdev> host$ virsh attach-device <domain> nvme-disk.xml --live On the guest, run fio benchmarks: guest$ fio --direct=1 --rw=randrw --refill_buffers --norandommap --randrepeat=0 --ioengine=libaio --bs=4k --rwmixread=100 --iodepth=16 --runtime=60 --name=job1 --filename=/dev/nvme0n1 --numjobs=4 Results are similar with numjobs=4 and numjobs=64, respectively: READ: bw=385MiB/s (404MB/s), 78.0MiB/s-115MiB/s (81.8MB/s-120MB/s), io=11.3GiB (12.1GB), run=30001-30001msec READ: bw=382MiB/s (400MB/s), 2684KiB/s-12.6MiB/s (2749kB/s-13.2MB/s), io=11.2GiB (12.0GB), run=30001-30009msec With the two patches applied, performance improved significantly for numjobs=4 and numjobs=64 cases, respectively: READ: bw=1191MiB/s (1249MB/s), 285MiB/s-309MiB/s (299MB/s-324MB/s), io=34.9GiB (37.5GB), run=30001-30001msec READ: bw=4273MiB/s (4481MB/s), 49.7MiB/s-113MiB/s (52.1MB/s-119MB/s), io=125GiB (134GB), run=30001-30005msec Userspace tool common name: qemu Userspace rpm: qemu The userspace tool has the following bit modes: 64-bit Userspace tool obtained from project website: na To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1847948/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
