I am trying to reduce the boot time of the imx6ull module. I have read and watched a few guides but I can’t make the boot fast enough. First of all I tried to reduce kernel size (5.27 to 4.04 MB) but the boot takes even longer (cca 3 s with logs enabled). Then I tried to make some changes in u-boot (disabling logs mostly) but this did not help either. So I thing I need to optimize rootfs and systemd, but is it possible to make boot on imx6ull less than 10 seconds?
We are developing a quite simple application which collects positions from GPS module and distributes them over LTE. The application itself is written in Java but I only need to reduce boot time (no need for Java VM). We also use some systemd services like resolv or networkd.
I attach output from grabserial for more info. grabserial log
If anyone could help me, I would be grateful.