------- Comment From ihch...@us.ibm.com 2019-12-16 15:02 EDT------- some summary we have so far
css-host-22 is p9/ac922 and css-host-130 is x86/hgx1 1. Device pass through P9/x86 similar performance Bare metal / VM similar performance 0.5GB/s to 1 GB/s for writes Up to 4-5 GB/s for reads Millions of int/csw per seconds for 4k page size and much smaller for 16 MB page size profiles Bare Metal http://css-host-22.watson.ibm.com/rundir/nvme_bm_perf_on_bm/20191004-103224/html/#/measurement/nvme_bm_perf_bm/css-host-22 http://css-host-130.watson.ibm.com/rundir/nvme_bm_perf_on_bm/20191210-132738/html/#/measurement/nvme_bm_perf_bm/css-host-130 Virtual Machine http://css-host-22.watson.ibm.com/rundir/nvme_vm_perf_vm/20191011-112156/html/#/measurement/vm/ubuntu http://css-host-130.watson.ibm.com/rundir/nvme_vm_perf_vm/20191210-223913/html/#/measurement/vm/ubuntu 2. file system pass through P9/x86 similar performance I/O bw achieved with 16MB page size, but very low I/O bw achieved with 4k page size CPU utilization is much lower on P9/AC922 On x86, CPU is waiting for some process to get to it (50% for qcow2 and 35% for raw) Int/csw Higher on x86 Higher with 4k page size Higher with raw profiles qcow2 http://css-host-130.watson.ibm.com/rundir/nvme_vm_perf_vm_qcow2/20191211-232233/html/#/measurement/vm/ubuntu http://css-host-22.watson.ibm.com/rundir/nvme_vm_perf_vm_qcow2/20191211-233729/html/#/measurement/vm/ubuntu raw http://css-host-130.watson.ibm.com/rundir/nvme_vm_perf_vm_raw/20191212-082717/html/#/measurement/vm/ubuntu http://css-host-22.watson.ibm.com/rundir/nvme_vm_perf_vm_raw/20191212-082810/html/#/measurement/vm/ubuntu 3. questions a. what is the diff between qcow2 and raw? how is that contributing to the cpu utilization? b. I have trouble configure scsci controller when I try to following the instructions: <controller type='scsi' index='0' model='virtio-scsi'> <address type='pci' domain='0x0000' bus='0x00' slot='0x0b' function='0x0'/> </controller> it gave me the argument is not available error c. for file system pass through, How to get better 4k performance? -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1853042 Title: Ubuntu 18.04 - vm disk i/o performance issue when using file system passthrough To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1853042/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
