Xen in systemd

sudo systemd-analyze critical-chain
The time after the unit is active or started is printed after the "@" character.
The time the unit takes to start is printed after the "+" character.

multi-user.target @44.185s
└─getty.target @44.184s
  └─getty@tty1.service @44.184s
    └─rc-local.service @44.078s +101ms
      └─xendomains.service @18.818s +25.257s
        └─lvm2-pvscan@8:33.service @2.038s +16.776s
          └─lvm2-lvmetad.socket @820ms
            └─-.mount
              └─system.slice
                └─-.slice