Configuring Priority Levels for Virtual Machines and Containers

In Parallels Cloud Server, you can configure the disk I/O (input/output) priority level of virtual machines and Containers. The higher the I/O priority level, the more time the virtual machine or Container will get for its disk I/O activities as compared to the other virtual machines and Containers on the Hardware Node. By default, any virtual machine or Container on the Hardware Node has the I/O priority level set to 4. However, you can change the current I/O priority level in the range from 0 to 7 using the --ioprio option of the prlctl set command. For example, you can issue the following command to set the I/O priority of Container 101 and the MyVM virtual machine to 6:

# prlctl set 101 --ioprio 6

# prlctl set MyVM --ioprio 6

To check the I/O priority level currently applied to Container 101 and the MyVM virtual machine, you can execute the following commands:

• For Container 101:

  # grep IOPRIO /etc/vz/conf/101.conf

  IOPRIO="6"

• For the MyVM virtual machine:

  # prlctl list --info | grep ioprio

  cpu 2 VT-x accl=high mode=32 cpuunits=1000 ioprio=6 iolimit=0