VIRTFS or VirtFS is a linux system process used to help manage the files on your system.

From linux-kvm.org:

VirtFS is a new paravirtualized filesystem interface designed for improving passthrough technologies in the KVM environment. It is based on the VirtIO framework and uses the 9P protocol.
Why use it?

  • virtualization aware filesystem
  • offers paravirtualized system services
  • simple passthrough for directories from host to guest
  • Backward/forward compatibility issues

Virtual Machine Manager integration since version 0.9.1

The /home/virtfs directory contains critical operating system files. If you
remove /home/virtfs, or any directories under /home/virtfs, you will cause
irreparable damage to your operating system. Do not remove /home/virtfs, or any
directories under /home/virtfs, unless you have tested, up-to-date backups.

You should ignore any disk usage warnings you receive that are associated with
the /home/virtfs directory!

For more information about the /home/virtfs directory, visit the documentation
at http://go.cpanel.net/virtfsdoc