search for: randread

...s not cache anything in guest > > and provides strong coherence. Other modes which provide less strong > > coherence and hence are faster are yet to be benchmarked. > > > > - Three fio ioengines psync, libaio and mmap have been used. > > > > - I/O Workload of randread, radwrite, seqread and seqwrite have been run. > > > > - Each file size is 2G. Block size 4K. iodepth=16 > > > > - "multi" means same operation was done with 4 jobs and each job is > > operating on a file of size 2G. > > > > - Some results are &...

...s not cache anything in guest > > and provides strong coherence. Other modes which provide less strong > > coherence and hence are faster are yet to be benchmarked. > > > > - Three fio ioengines psync, libaio and mmap have been used. > > > > - I/O Workload of randread, radwrite, seqread and seqwrite have been run. > > > > - Each file size is 2G. Block size 4K. iodepth=16 > > > > - "multi" means same operation was done with 4 jobs and each job is > > operating on a file of size 2G. > > > > - Some results are &...

...tio-blk-pci,scsi=off,bus=pci.0,addr=0x6,drive=drive-virtio-disk0,id=virtio-disk0,bootindex=1,write-cache=on > > > > > > > > If I add "-device > > > > virtio-serial-pci,id=virtio-serial0,bus=pci.0,addr=0x5 ", the virtio > > > > disk 4k iops (randread/randwrite) would downgrade from 60k to 40k. > > > > > > > > In VM, if I rmmod virtio-console, the performance will back to normal. > > > > > > > > Any idea about this issue? > > > > > > > > I don't know this is a qemu issue...

...u-kvm), the patch can increase I/O performance a lot with VIRTIO_RING_F_EVENT_IDX enabled: - without the patch: 14K IOPS - with the patch: 34K IOPS fio script: [global] direct=1 bsrange=4k-4k timeout=10 numjobs=4 ioengine=libaio iodepth=64 filename=/dev/vdc group_reporting=1 [f1] rw=randread Cc: Rusty Russell <rusty at rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst at redhat.com> Cc: virtualization at lists.linux-foundation.org Signed-off-by: Ming Lei <ming.lei at canonical.com> --- drivers/block/virtio_blk.c | 9 ++++++--- 1 file changed, 6 insertions(...

...u-kvm), the patch can increase I/O performance a lot with VIRTIO_RING_F_EVENT_IDX enabled: - without the patch: 14K IOPS - with the patch: 34K IOPS fio script: [global] direct=1 bsrange=4k-4k timeout=10 numjobs=4 ioengine=libaio iodepth=64 filename=/dev/vdc group_reporting=1 [f1] rw=randread Cc: Rusty Russell <rusty at rustcorp.com.au> Cc: "Michael S. Tsirkin" <mst at redhat.com> Cc: virtualization at lists.linux-foundation.org Signed-off-by: Ming Lei <ming.lei at canonical.com> --- drivers/block/virtio_blk.c | 9 ++++++--- 1 file changed, 6 insertions(...

On Fri, Nov 02, 2018 at 06:21:22PM +0000, Vitaly Mayatskikh wrote: > vhost_blk is a host-side kernel mode accelerator for virtio-blk. The > driver allows VM to reach a near bare-metal disk performance. See IOPS > numbers below (fio --rw=randread --bs=4k). > > This implementation uses kiocb interface. It is slightly slower than > going directly through bio, but is simpler and also works with disk > images placed on a file system. > > # fio num-jobs > # A: bare metal over block > # B: bare metal over file > # C:...

On 2018/11/3 ??2:21, Vitaly Mayatskikh wrote: > vhost_blk is a host-side kernel mode accelerator for virtio-blk. The > driver allows VM to reach a near bare-metal disk performance. See IOPS > numbers below (fio --rw=randread --bs=4k). > > This implementation uses kiocb interface. It is slightly slower than > going directly through bio, but is simpler and also works with disk > images placed on a file system. > > # fio num-jobs > # A: bare metal over block > # B: bare metal over file > # C: vi...

On 2018/11/3 ??2:21, Vitaly Mayatskikh wrote: > vhost_blk is a host-side kernel mode accelerator for virtio-blk. The > driver allows VM to reach a near bare-metal disk performance. See IOPS > numbers below (fio --rw=randread --bs=4k). > > This implementation uses kiocb interface. It is slightly slower than > going directly through bio, but is simpler and also works with disk > images placed on a file system. > > # fio num-jobs > # A: bare metal over block > # B: bare metal over file > # C: vi...

...node 1) so that memory is in the wrong NUMA node for the virtio-blk-pci devic= > > e. > > Applying these patches fixes memory placement so that virtqueues and driver > > state is allocated in vNUMA node 1 where the virtio-blk-pci device is located. > > > > The fio 4KB randread benchmark results do not show a significant improvement: > > > > Name IOPS Error > > virtio-blk 42373.79 =C2=B1 0.54% > > virtio-blk-numa 42517.07 =C2=B1 0.79% > > > I remember I did something similar in vhost by using page_to_nid() fo...

...node 1) so that memory is in the wrong NUMA node for the virtio-blk-pci devic= > > e. > > Applying these patches fixes memory placement so that virtqueues and driver > > state is allocated in vNUMA node 1 where the virtio-blk-pci device is located. > > > > The fio 4KB randread benchmark results do not show a significant improvement: > > > > Name IOPS Error > > virtio-blk 42373.79 =C2=B1 0.54% > > virtio-blk-numa 42517.07 =C2=B1 0.79% > > > I remember I did something similar in vhost by using page_to_nid() fo...

...lti-vq feature, 'num_queues=N' need to be added into >> '-device virtio-blk-pci ...' of qemu command line, and suggest to pass >> 'vectors=N+1' to keep one MSI irq vector per each vq, and the feature >> depends on x-data-plane. >> >> Fio(libaio, randread, iodepth=64, bs=4K, jobs=N) is run inside VM to >> verify the improvement. >> >> I just create a small quadcore VM and run fio inside the VM, and >> num_queues of the virtio-blk device is set as 2, but looks the >> improvement is still obvious. The host is 2 sockets, 8...

...lti-vq feature, 'num_queues=N' need to be added into >> '-device virtio-blk-pci ...' of qemu command line, and suggest to pass >> 'vectors=N+1' to keep one MSI irq vector per each vq, and the feature >> depends on x-data-plane. >> >> Fio(libaio, randread, iodepth=64, bs=4K, jobs=N) is run inside VM to >> verify the improvement. >> >> I just create a small quadcore VM and run fio inside the VM, and >> num_queues of the virtio-blk device is set as 2, but looks the >> improvement is still obvious. The host is 2 sockets, 8...

...e() code run on vCPU 0 in vNUMA node 0 (host NUMA node 1) so that memory is in the wrong NUMA node for the virtio-blk-pci devic= e. Applying these patches fixes memory placement so that virtqueues and driver state is allocated in vNUMA node 1 where the virtio-blk-pci device is located. The fio 4KB randread benchmark results do not show a significant improvement: Name IOPS Error virtio-blk 42373.79 =C2=B1 0.54% virtio-blk-numa 42517.07 =C2=B1 0.79% Stefan Hajnoczi (3): virtio-pci: use NUMA-aware memory allocation in probe virtio_ring: use NUMA-aware memory allocation...

...e() code run on vCPU 0 in vNUMA node 0 (host NUMA node 1) so that memory is in the wrong NUMA node for the virtio-blk-pci devic= e. Applying these patches fixes memory placement so that virtqueues and driver state is allocated in vNUMA node 1 where the virtio-blk-pci device is located. The fio 4KB randread benchmark results do not show a significant improvement: Name IOPS Error virtio-blk 42373.79 =C2=B1 0.54% virtio-blk-numa 42517.07 =C2=B1 0.79% Stefan Hajnoczi (3): virtio-pci: use NUMA-aware memory allocation in probe virtio_ring: use NUMA-aware memory allocation...

...it #v2.0.0-virtblk-mq.1 For enabling the multi-vq feature, 'num_queues=N' need to be added into '-device virtio-blk-pci ...' of qemu command line, and suggest to pass 'vectors=N+1' to keep one MSI irq vector per each vq, and the feature depends on x-data-plane. Fio(libaio, randread, iodepth=64, bs=4K, jobs=N) is run inside VM to verify the improvement. I just create a small quadcore VM and run fio inside the VM, and num_queues of the virtio-blk device is set as 2, but looks the improvement is still obvious. 1), about scalability - without mutli-vq feature -- jobs=2, though...

...it #v2.0.0-virtblk-mq.1 For enabling the multi-vq feature, 'num_queues=N' need to be added into '-device virtio-blk-pci ...' of qemu command line, and suggest to pass 'vectors=N+1' to keep one MSI irq vector per each vq, and the feature depends on x-data-plane. Fio(libaio, randread, iodepth=64, bs=4K, jobs=N) is run inside VM to verify the improvement. I just create a small quadcore VM and run fio inside the VM, and num_queues of the virtio-blk device is set as 2, but looks the improvement is still obvious. 1), about scalability - without mutli-vq feature -- jobs=2, though...

...MA node 0 (host NUMA > node 1) so that memory is in the wrong NUMA node for the virtio-blk-pci devic= > e. > Applying these patches fixes memory placement so that virtqueues and driver > state is allocated in vNUMA node 1 where the virtio-blk-pci device is located. > > The fio 4KB randread benchmark results do not show a significant improvement: > > Name IOPS Error > virtio-blk 42373.79 =C2=B1 0.54% > virtio-blk-numa 42517.07 =C2=B1 0.79% I remember I did something similar in vhost by using page_to_nid() for descriptor ring. And I get little...

...en virtual machine write to disk and run blktrace from dom0 like this blktrace -w 60 -d /dev/disk/vbd/21-920 -o - > test.trace /dev/disk/vbd/21-920 is the software raid contains 2 lv volumes , each lv volume created in big srp attached disk Inside vm i try to do some work via fio: [global] rw=randread size=128m directory=/tmp ioengine=libaio iodepth=4 invalidate=1 direct=1 [bgwriter] rw=randwrite iodepth=32 [queryA] iodepth=1 ioengine=mmap direct=0 thinktime=3 [queryB] iodepth=1 ioengine=mmap direct=0 thinktime=5 [bgupdater] rw=randrw iodepth=16 thinktime=40 size=128m After that i try to ge...

...enabled: > - without the patch: 14K IOPS > - with the patch: 34K IOPS > > fio script: > [global] > direct=1 > bsrange=4k-4k > timeout=10 > numjobs=4 > ioengine=libaio > iodepth=64 > > filename=/dev/vdc > group_reporting=1 > > [f1] > rw=randread > > Cc: Rusty Russell <rusty at rustcorp.com.au> > Cc: "Michael S. Tsirkin" <mst at redhat.com> > Cc: virtualization at lists.linux-foundation.org > Signed-off-by: Ming Lei <ming.lei at canonical.com> Acked-by: Rusty Russell <rusty at rustcorp.com.au&g...

...bled: > - without the patch: 14K IOPS > - with the patch: 34K IOPS > > fio script: > [global] > direct=1 > bsrange=4k-4k > timeout=10 > numjobs=4 > ioengine=libaio > iodepth=64 > > filename=/dev/vdc > group_reporting=1 > > [f1] > rw=randread > > Cc: Rusty Russell <rusty at rustcorp.com.au> > Cc: "Michael S. Tsirkin" <mst at redhat.com> > Cc: virtualization at lists.linux-foundation.org > Signed-off-by: Ming Lei <ming.lei at canonical.com> Acked-by: Michael S. Tsirkin <mst at redhat.com&gt...