Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-03-04 Thread Steffen Thorhauer
Hi, higher /sys/block/vda/queue/read_ahead_kb inside the VM tip from Wido den Hollander helped me a lot, but I don't remember, why I needed several tries to get it really running. You may also read the "[ceph-users] RBD+KVM problems with sequential read" thread: http://lists.ceph.com/pipermai

Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-03-03 Thread Patrik Plank
Hi, have the same problem with rbd/kvm. Did you find a solution? I would appreciate for every helpful hint. best regards ___ ceph-users mailing list ceph-users@lists.ceph.com http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com

Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-01-10 Thread Steffen Thorhauer
On 01/10/2014 03:31 PM, Ирек Фасихов wrote: ceph osd dump, please. epoch 7834 fsid 2eaf04ca-b59c-4622-83b0-45a63aea3b9b created 2013-07-30 15:29:16.012846 modified 2014-01-09 12:13:31.828996 flags pool 0 'data' rep size 2 min_size 1 crush_ruleset 0 object_hash rjenkins pg_num 64 pgp_num 64

Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-01-10 Thread Ирек Фасихов
ceph osd dump, please. 10 янв. 2014 г. 18:29 пользователь "Steffen Thorhauer" < steffen.thorha...@iti.cs.uni-magdeburg.de> написал: > On 01/10/2014 02:35 PM, Wido den Hollander wrote: > > > > > > Op 10 jan. 2014 om 18:49 heeft "Steffen Thorhauer" < > steffen.thorha...@iti.cs.uni-magdeburg.de> het

Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-01-10 Thread Steffen Thorhauer
On 01/10/2014 02:35 PM, Wido den Hollander wrote: Op 10 jan. 2014 om 18:49 heeft "Steffen Thorhauer" > het volgende geschreven: On 01/10/2014 01:21 PM, Ирек Фасихов wrote: You need to use VirtIO. with this parameter ist not a real p

Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-01-10 Thread Wido den Hollander
> Op 10 jan. 2014 om 18:49 heeft "Steffen Thorhauer" > het volgende geschreven: > >> On 01/10/2014 01:21 PM, Ирек Фасихов wrote: >> You need to use VirtIO. >> >> > with this parameter ist not a real performance increase: > dd if=/dev/zero of=zerofile-2 bs=1G count=8 > 8+0 records in >

Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-01-10 Thread Steffen Thorhauer
On 01/10/2014 01:21 PM, Ирек Фасихов wrote: You need to use VirtIO. with this parameter ist not a real performance increase: dd if=/dev/zero of=zerofile-2 bs=1G count=8 8+0 records in 8+0 records out 8589934592 bytes (8.6 GB) copied, 73.8425 s, 116 MB/s and reading: trompete@multius:~$ dd

Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-01-10 Thread Carl-Johan Schenström
On 2014-01-10 13:21, Ирек Фасихов wrote: You need to use VirtIO. According to , virtio doesn't support discard/TRIM. However, it seems like virtio-scsi supports discard. Is it possible to use virtio-scsi to get *both* per

Re: [ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-01-10 Thread Ирек Фасихов
You need to use VirtIO. 2014/1/10 > Hi, > I'm using a 1GBit network. 16 osd on 8 hosts with xfs and journal on ssd. > I have a read performance problem in a libvirt kvm/qemu/rbd VM > on a ceph client host. All involved hosts are ubuntu 13.10. Ceph is 72.2. > The only VM disk is a rbd vol

[ceph-users] libvirt qemu/kvm/rbd inside VM read slow

2014-01-10 Thread steffen . thorhauer
Hi, I'm using a 1GBit network. 16 osd on 8 hosts with xfs and journal on ssd. I have a read performance problem in a libvirt kvm/qemu/rbd VM on a ceph client host. All involved hosts are ubuntu 13.10. Ceph is 72.2. The only VM disk is a rbd volume: