Re: [ovirt-users] How do I get discard working?
Looks like I need to learn how to use VDSM hooks. I'll start there. Thanks everyone. On 06/10/2015 04:18 PM, Amador Pahim wrote: On 06/10/2015 03:24 PM, Fabian Deutsch wrote: - Original Message - oVirt Node - 3.5 - 0.999.201504280931.el7.centos Using our shared storage via baremetal (stock CentOS 7) -> iscsi, I can successfully issue fstrim commands. With oVirt at the VM level, even with direct LUNS, trim commands are not supported despite having the LVM config in the VMs set up to allow it. Hey, IIUIC you try to get discard working for VMs? That means that if fstrim is used inside the VM, that it is getting passed down? The command line needed for qemu to support discards is: $ qemu … -drive if=virtio,cache=unsafe,discard,file= … I'm not sure which qemu disk drivers/busses support this, but at least virtio does so. I'm using it for development. You could try a vdsm hook to modify the qemu command which is called when the VM is spawned. Let me know if you can come up with a hook to realize this! There's this hook in code review intended to do so: https://gerrit.ovirt.org/#/c/29770/ Greetings fabian ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Re: [ovirt-users] How do I get discard working?
On 06/10/2015 03:24 PM, Fabian Deutsch wrote: - Original Message - oVirt Node - 3.5 - 0.999.201504280931.el7.centos Using our shared storage via baremetal (stock CentOS 7) -> iscsi, I can successfully issue fstrim commands. With oVirt at the VM level, even with direct LUNS, trim commands are not supported despite having the LVM config in the VMs set up to allow it. Hey, IIUIC you try to get discard working for VMs? That means that if fstrim is used inside the VM, that it is getting passed down? The command line needed for qemu to support discards is: $ qemu … -drive if=virtio,cache=unsafe,discard,file= … I'm not sure which qemu disk drivers/busses support this, but at least virtio does so. I'm using it for development. You could try a vdsm hook to modify the qemu command which is called when the VM is spawned. Let me know if you can come up with a hook to realize this! There's this hook in code review intended to do so: https://gerrit.ovirt.org/#/c/29770/ Greetings fabian ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Re: [ovirt-users] How do I get discard working?
Once upon a time, Fabian Deutsch said: > I'm not sure which qemu disk drivers/busses support this, but at least virtio > does so. > I'm using it for development. Using CentOS 7, I think qemu-kvm only supports discard on virtio-scsi drives using the raw format. Discard on qcow2 images is supported for newer versions of qemu-kvm. oVirt uses virtio by default; you can switch to virtio-scsi. However, if you use thin-provisioned disks, oVirt uses qcow2 format, so discard is not supported with CentOS 7's version of qemu-kvm. -- Chris Adams ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
Re: [ovirt-users] How do I get discard working?
- Original Message - > oVirt Node - 3.5 - 0.999.201504280931.el7.centos > > Using our shared storage via baremetal (stock CentOS 7) -> iscsi, I can > successfully issue fstrim commands. With oVirt at the VM level, even > with direct LUNS, trim commands are not supported despite having the LVM > config in the VMs set up to allow it. Hey, IIUIC you try to get discard working for VMs? That means that if fstrim is used inside the VM, that it is getting passed down? The command line needed for qemu to support discards is: $ qemu … -drive if=virtio,cache=unsafe,discard,file= … I'm not sure which qemu disk drivers/busses support this, but at least virtio does so. I'm using it for development. You could try a vdsm hook to modify the qemu command which is called when the VM is spawned. Let me know if you can come up with a hook to realize this! Greetings fabian ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
[ovirt-users] How do I get discard working?
oVirt Node - 3.5 - 0.999.201504280931.el7.centos Using our shared storage via baremetal (stock CentOS 7) -> iscsi, I can successfully issue fstrim commands. With oVirt at the VM level, even with direct LUNS, trim commands are not supported despite having the LVM config in the VMs set up to allow it. Thanks -- This email was Virus checked by the PHX UTM 9. For issues please contact the Windows Systems Admin. ___ Users mailing list Users@ovirt.org http://lists.ovirt.org/mailman/listinfo/users
