Note
This feature is available starting from the MCP 2019.2.4 maintenance update. Before enabling the feature, follow the steps described in Apply maintenance updates.
To prevent excessive disk consumption while clearing ephemeral
LVM volumes using shred, you can set the ionice level for the ephemeral
LVM volume shred
operation in nova-compute
.
Setting of the ionice level described below makes sense if:
nova:compute:lvm:ephemeral
is set to True
nova:compute:lvm:volume_clear
is set to zero
or shred
To set the ionice level:
Log in to the Salt Master node.
In classes/cluster/<cluster_name>/openstack/compute.yml
, set
the level for volume_clear_ionice_level
as required:
nova:
compute:
lvm:
volume_clear_ionice_level: <level>
Possible <level>
values are as follows:
idle
- to use the idle
scheduling class. This option impacts
system performance the least with a downside of increased time
for a volume clearance.0
to 7
- to use the best-effort scheduling class.
Set the priority level to the specified number.Apply the changes:
salt -C 'I@nova:compute' state.sls nova.compute