Tips and tweaks for reducing Linux startup time
Ready Set Go

Today's Linux systems boot faster than ever, but many users still get impatient waiting for that first glimpse of desktop. These tweaks will help you get a faster start from the bootloader and kernel.
CPUs, RAM modules, and storage media keep getting faster, but today's Linux systems are still a little too slow at startup for many busy users. With a few useful tools and a little knowledge of the Linux environment, you can shave some seconds from the startup process. Read on for some insights.
systemd-analyze
The systemd-analyze
tool supplied with systemd gives a first impression of where time is being wasted. The time
option outputs the total startup time and shows what portion of that time is used for firmware, bootloader, kernel, and user space:
systemd-analyze time
Listing 1 shows the output, which will vary depending on you firmware, hardware, and software configuration.
Listing 1
Analyzing Start Time
$ systemd-analyze time Startup finished in 3.393s (firmware) + 10.554s (loader) + 2.123s (kernel) + 4.789s (userspace) = 20.860s graphical.target reached after 4.778s in userspace
Test Setup
The test system for this article was a four-year-old Tuxedo BU1406 with a "Kaby Lake" Intel i7-7500U CPU, 32GB DDR4 RAM, and a 512GB NVMe SSD; this machine cost around a thousand dollars when it was new. The operating system was a Debian "Bullseye" ("Testing") from November 19, 2020 with a 5.9.9 kernel and systemd 246.6 set up by the Debian installer. The standard system with Gnome 3.38.1, GDM 3.38.2, and an OpenSSH server provides the user interface. Our focus was primarily on systems with UEFI firmware, which is common now on most modern hardware.
Our goal was to minimize the startup time based on the readings for firmware, loader, and kernel in the systemd-analyze
output. Older systems with significantly longer default boot times typically offer far more potential to improve the boot speed.
Firmware
Users typically have few options to optimize the firmware, because it is often proprietary and only the device manufacturer can change and distribute it. In the default Debian configuration used on the test system, the UEFI firmware starts the GRUB bootloader. Other distributions might use the alternative systemd-boot
boot manager in place of GRUB.
UEFI firmware is now ubiquitous on x86 systems. The startup screen typically announces which key or key pattern you need to press to access firmware settings. In the graphical firmware menu, you can look for functions that slow down the system, like network boot, and turn them off if they are not needed. Some systems even offer option for a faster startup, like Quick Boot or Fast Boot.
Aside from the lack of source code – and thus, lack of freedom – the size of the UEFI firmware is also a major criticism. Alternatives include coreboot for x86 systems, as well as U-Boot and coreboot for ARM systems. Coreboot lets you initialize only enough hardware to boot the operating system. Coreboot firmware is used in Chromebooks and on devices by vendors such as System76 and Purism. The minimal approach results in firmware startup times of less than a second, or even as little as 500ms for some devices.
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
Direct Download
Read full article as PDF:
Price $2.95
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Find SysAdmin Jobs
News
-
MNT Seeks Financial Backing for New Seven-Inch Linux Laptop
MNT Pocket Reform is a tiny laptop that is modular, upgradable, recyclable, reusable, and ships with Debian Linux.
-
Ubuntu Flatpak Remix Adds Flatpak Support Preinstalled
If you're looking for a version of Ubuntu that includes Flatpak support out of the box, there's one clear option.
-
Gnome 44 Release Candidate Now Available
The Gnome 44 release candidate has officially arrived and adds a few changes into the mix.
-
Flathub Vying to Become the Standard Linux App Store
If the Flathub team has any say in the matter, their product will become the default tool for installing Linux apps in 2023.
-
Debian 12 to Ship with KDE Plasma 5.27
The Debian development team has shifted to the latest version of KDE for their testing branch.
-
Planet Computers Launches ARM-based Linux Desktop PCs
The firm that originally released a line of mobile keyboards has taken a different direction and has developed a new line of out-of-the-box mini Linux desktop computers.
-
Ubuntu No Longer Shipping with Flatpak
In a move that probably won’t come as a shock to many, Ubuntu and all of its official spins will no longer ship with Flatpak installed.
-
openSUSE Leap 15.5 Beta Now Available
The final version of the Leap 15 series of openSUSE is available for beta testing and offers only new software versions.
-
Linux Kernel 6.2 Released with New Hardware Support
Find out what's new in the most recent release from Linus Torvalds and the Linux kernel team.
-
Kubuntu Focus Team Releases New Mini Desktop
The team behind Kubuntu Focus has released a new NX GEN 2 mini desktop PC powered by Linux.