Dom0 Customization

Copy/paste Key Combination

Use super + c for copying:

qvm-features dom0 gui-default-secure-copy-sequence Mod4-c

Use super + v for pasting:

qvm-features dom0 gui-default-secure-paste-sequence Mod4-v

The default is ctrl + shift + c and crtl + shift + v which are already used in terminals and for raw pasting.

Number of VM Snapshots to Keep

A snapshot is created on every VM bootup. By default, the last three are kept.

Increase default number of snapshots to five:

qvm-pool set vm-pool -o revisions_to_keep=5

Show current configuration:

qvm-pool info vm-pool

Tip

Change number of snapshots for root volume (/):

Only useful for TemplateVMs and StandaloneVMs. AppVMs use a volatile copy of a TemplateVM.

Set:

qvm-volume set <vm>:root revisons_to_keep <N>

Show config:

qvm-volume info <vm>:root

Change number of snapshots for private volume (/rw/):

On Qubes, /home/ is also stored in /rw/.

Set:

qvm-volume set <vm>:private revisons_to_keep <N>

Show config:

qvm-volume info <vm>:private

TRIM / Discard

Pass discard through to physical disk:

  1. Find LUKS device:

    dmsetup ls --target crypt

  2. Enable discard:

    cryptsetup refresh --allow-discards <device>

Discard free space on lvremove(8):

  1. Set in /etc/lvm/lvm.conf:

    issue_discards = 1

See also:

Kernel Parameters Dom0

Add to /etc/default/grub:

GRUB_CMDLINE_LINUX="$GRUB_CMDLINE_LINUX random.trust_cpu=off"

Kernel Parameters Qubes

Set kernel parameters:

qvm-prefs <vm> kernelopts 'random.trust_cpu=off vsyscall=none'

Set on template and AppVMs will inherit.

Tip

List parameters for all VMs:

qvm-ls --fields name,kernelopts