Measure boot time, find the slow services, and visualize the startup sequence with a single tool. 21.06.2026 | reading time: 2 min systemd-analyze tells you where boot time goes and which services are responsible; use it to measure firmware, kernel and userspace durations and to start pruning delays right away. Find the culprit now A sysadmin notices a long startup and runs these commands to inspect the timeline and the slowest units: ```\n$ systemd-analyze\nStartup finished in 200ms (firmware) 120ms (loader) 80ms (kernel) 1.450s (userspace) = 1.850s\n\n$ systemd-analyze blame | head -n 6\n 1.450s docker.service\n 0.300s apt-daily.service\n 0.120s NetworkManager.service\n 0.050s dev-sda1.device\n\n$ systemd-analyze critical-chain docker.service\ndocker.service @1.100s +0.350s\n└─network.target @0.900s\n``` Do more than time it Generate an SVG timeline with `systemd-analyze plot > boot.svg` to inspect overlaps, use `systemd-analyze dot` to create Graphviz graphs, run `systemd-analyze verify` to check unit files and `systemd-analyze security` to get per-unit security settings; interpret the split between firmware, kernel and userspace times and then disable, mask or parallelize the slow units you found. Combine evidence from logs After spotting a slow unit, run `journalctl -u <unit>` and `systemctl status <unit>` to read logs and state, then iterate: stop the unit, tweak its unit file, or adjust StartLimit and dependencies to speed startup. Wrap up and next steps Measure, act, measure again — that cycle yields fast, predictable boots; if he wants to formalize skills consider CompTIA Linux+ or LPIC-1, and check bitsandbytes.academy for intensive exam preparation. Join Bits & Bytes Academy First class LINUX exam preparation. boot-process troubleshooting utilities
