I was putting Home Assistant OS on a spare Raspberry Pi 4, booting off a USB SSD, with an HDMI capture card plugged into the board so I could watch the boot on my main monitor. I powered it on, console output started scrolling, and about four and a half seconds in the screen went to NO SIGNAL and stayed there. Every boot attempt did the same thing.
I've been working on ARM images lately. They are not application containers, but a distro-style image built from ubuntu:22.04 that installs large package sets, runs post-install scripts, enables services, and pulls NVIDIA repositories. It's much closer to OS assembly than a typical app container.
I wasn't surprised that building these images natively on ARM would be faster than doing it from an x86 machine using emulation. That part was expected.
What surprised me was how much faster it was.
Seeing a Raspberry Pi 5 consistently outperform a 3-year-old high-end Intel laptop by almost 2x forced me to re-evaluate some assumptions I had about build performance, hardware specs, and what "powerful enough" actually means when you're building ARM software.
When the Raspberry Pi5 is turned on, it will check on which device it is configured to boot. By default, this is the SD card, but you can change it to boot from an NVMe or USB drive while still fallback to SD. In my case, I’m using a USB SSD. Let’s take a look at how the disk is partitioned.