Inspect where time is spent during boot and act on concrete slow services. 16.11.2025 | reading time: 2 min Ever wondered why a machine takes too long to reach a usable desktop or service? systemd-analyze turns that question into actionable facts by measuring how much time firmware, kernel, initrd and userspace take and by listing the services that dominate startup time. Investigate a slow boot Run these commands and inspect the output to find slow units; for reproducibility save the SVG and open it in a browser: ```systemd-analyze Startup finished in 3.412s (firmware) + 0.842s (loader) + 1.764s (kernel) + 5.203s (userspace) = 11.221s systemd-analyze blame 4.200s NetworkManager-wait-online.service 2.350s docker.service 1.120s dev-sda1.device 0.900s sshd.service systemd-analyze critical-chain graphical.target @5.203s └─multi-user.target @5.203s └─NetworkManager-wait-online.service @0.800s +4.200s └─docker.service @2.350s +2.350s systemd-analyze plot > boot.svg ``` Options that matter Start with the simple summary, then run blame to order slow units and critical-chain to see serial dependencies; export a plot to SVG for a timeline view and use verify to check unit file correctness; when a single service blocks boot, mask it, adjust Wants/After relationships or convert it to a socket-activated unit to shorten boot paths. Pair with these tools Use journalctl -b to read boot logs and catch error messages, use systemctl to inspect and change unit states and dependencies, and use dmesg for early kernel messages that systemd-analyze cannot attribute to a userspace unit. Next steps and impact Measure before and after each change and automate the checks in a script to make improvements repeatable; reducing a few seconds on many machines multiplies into significant operational savings, and if you want to deepen skills consider studying for CompTIA Linux+ or LPIC-1 with intensive exam preparation at bitsandbytes.academy to turn practical know-how into certification. Join Bits & Bytes Academy First class LINUX exam preparation. boot-process utilities troubleshooting processes
