![Stephen Finucane](/assets/img/avatar_default.png)
These are in the cinder doc tree so of course they're block storage-related. Change-Id: Ic1950ff89021a89de397619eef17f8100eb3d847 Signed-off-by: Stephen Finucane <stephenfin@redhat.com>
2.8 KiB
Configure and use volume number weigher
OpenStack Block Storage enables you to choose a volume back end
according to free_capacity
and
allocated_capacity
. The volume number weigher feature lets
the scheduler choose a volume back end based on its volume number in the
volume back end. This can provide another means to improve the volume
back ends' I/O balance and the volumes' I/O performance.
Enable volume number weigher
To enable a volume number weigher, set the
scheduler_default_weighers
to
VolumeNumberWeigher
flag in the cinder.conf
file to define VolumeNumberWeigher
as the selected
weigher.
Configure multiple-storage back ends
To configure VolumeNumberWeigher
, use
LVMVolumeDriver
as the volume driver.
This configuration defines two LVM volume groups:
stack-volumes
with 10 GB capacity and
stack-volumes-1
with 60 GB capacity. This example
configuration defines two back ends:
scheduler_default_weighers=VolumeNumberWeigher
enabled_backends=lvmdriver-1,lvmdriver-2
[lvmdriver-1]
volume_group=stack-volumes
volume_driver=cinder.volume.drivers.lvm.LVMVolumeDriver
volume_backend_name=LVM
[lvmdriver-2]
volume_group=stack-volumes-1
volume_driver=cinder.volume.drivers.lvm.LVMVolumeDriver
volume_backend_name=LVM
Volume type
Define a volume type in Block Storage:
$ openstack volume type create lvm
Create an extra specification that links the volume type to a back-end name:
$ openstack volume type set lvm --property volume_backend_name=LVM
This example creates a lvm volume type with
volume_backend_name=LVM
as extra specifications.
Usage
To create six 1-GB volumes, run the openstack volume create --size 1 --type lvm volume1
command six times:
$ openstack volume create --size 1 --type lvm volume1
This command creates three volumes in stack-volumes
and
three volumes in stack-volumes-1
.
List the available volumes:
# lvs
LV VG Attr LSize Pool Origin Data% Move Log Copy% Convert
volume-3814f055-5294-4796-b5e6-1b7816806e5d stack-volumes -wi-a---- 1.00g
volume-72cf5e79-99d2-4d23-b84e-1c35d3a293be stack-volumes -wi-a---- 1.00g
volume-96832554-0273-4e9d-902b-ad421dfb39d1 stack-volumes -wi-a---- 1.00g
volume-169386ef-3d3e-4a90-8439-58ceb46889d9 stack-volumes-1 -wi-a---- 1.00g
volume-460b0bbb-d8a0-4bc3-9882-a129a5fe8652 stack-volumes-1 -wi-a---- 1.00g
volume-9a08413b-0dbc-47c9-afb8-41032ab05a41 stack-volumes-1 -wi-a---- 1.00g