> On 26 Jun 2018, at 14.04, Damian Dabrowski <scooty96@xxxxxxxxx> wrote: > > Hi Stefan, thanks for reply. > > Unfortunately it didn't work. > > disk config: > <disk type='network' device='disk'> > <driver name='qemu' type='raw' cache='directsync' io='native' discard='unmap'/> > <auth username='compute'> > <secret type='ceph' uuid='a5d0dd94-57c4-ae55-ffe0-7e3732a24455'/> > </auth> > <source protocol='rbd' name='volumes-nvme/volume-ce247187-a625-49f1-bacd-fc03df215395'> > <host name='172.31.0.1' port='6789'/> > <host name='172.31.0.2' port='6789'/> > <host name='172.31.0.3' port='6789'/> > </source> > <target dev='sdb' bus='scsi'/> > <serial>ce247187-a625-49f1-bacd-fc03df215395</serial> > <address type='drive' controller='0' bus='0' target='0' unit='2'/> > </disk> > > > Controller config: > <controller type='scsi' index='0' model='virtio-scsi'> > <driver queues='8'/> > <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> > </controller> > > > benchmark command: fio --randrepeat=1 --ioengine=libaio --direct=1 --name=test --filename=test --bs=4k --iodepth=64 --size=1G --readwrite=randwrite --time_based --runtime=60 --write_iops_log=write_results --numjobs=8 > > And I'm still getting very low random write IOPS inside KVM instance with 8vcores(3-5k compared to 20k+ outside KVM) > > Maybe do You have any idea how to deal with it? What about trying with io=‘threads’ and/or maybe cache=’none’ or swap from virtio-scsi to blk-mq? Other people had similar issues, try asking ‘G’ https://serverfault.com/questions/425607/kvm-guest-io-is-much-slower-than-host-io-is-that-normal https://wiki.mikejung.biz/KVM_/_Xen /Steffen _______________________________________________ ceph-users mailing list ceph-users@xxxxxxxxxxxxxx http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com