In my experience, booting using single threaded inits (at least in their early stages) actually speeds up the process. The overhead from multithreaded startup on something as simple as an init system can hurt startup performance, especially on older CPUs.
Of course you need a CPU capable of multi threading, which today means any CPU, but then there is no doubt that the multithreaded init process is way faster.
This was thoroughly tested when systemd demonstrated it.
Single threaded init processes have bottlenecks, and a single issue will stall the whole process. Of course systemd only influence boot speed of user space, but the Linux kernel itself is also multithreaded in it’s boot processes today, because it is without a doubt faster.
In my experience, booting using single threaded inits (at least in their early stages) actually speeds up the process. The overhead from multithreaded startup on something as simple as an init system can hurt startup performance, especially on older CPUs.
Of course you need a CPU capable of multi threading, which today means any CPU, but then there is no doubt that the multithreaded init process is way faster.
This was thoroughly tested when systemd demonstrated it.
Single threaded init processes have bottlenecks, and a single issue will stall the whole process. Of course systemd only influence boot speed of user space, but the Linux kernel itself is also multithreaded in it’s boot processes today, because it is without a doubt faster.