這是本文件的舊版！
Systemd
boot time analyze
systemd-analyze
systemd-analyze systemd-analyze blame systemd-analyze plot > /tmp/plot.svg
systemd-bootchart
systemd-bootchart
https://wiki.gentoo.org/wiki/Systemd#systemd-bootchart
https://wiki.archlinux.org/index.php/Improving_performance/Boot_process#Analyzing_the_boot_process
process
systemd-cgls pstree
