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3.3. Virtual Disk Performance Options

Several virtual disk related options are available to your guest virtual machines during installation that can impact performance. The following image shows the virtual disk options available to your guests.
The cache mode, IO mode, and IO tuning can be selected in the Virtual Disk section in virt-manager. Set these parameters in the fields under Performance options, as shown in the following image:
Virtual Disk Performance Options

Figure 3.7. Virtual Disk Performance Options

Important

When setting the virtual disk performance options in virt-manager, the virtual machine must be restarted for the settings to take effect.
See Section 7.2, “Caching” and Section 7.3, “I/O Mode” for descriptions of these settings and instructions for editing these settings in the guest XML configuration.