AmigaROM for AmigaOS4

[Rogue]

Amiga would boot to a ready state in less than 5 seconds from cold boot

Huh? Only if you would just switch it on and let it skip startup-sequence. "Back in the day" there where 3.5 inch floppy disks where the seek already took 5 seconds.

We need a computer today that can be ready within 5 seconds of a cold boot. Waiting for the computer to boot to a ready state is old and time-consuming.

Not really, if the machine and OS is stable you will not reboot too often.

Is there any possibility that this will ever be achieved again? Particularly with AmigaOS4 or AmigaOS5? AmigaOS has a small footprint, so how about an embedded ROM that works with AmigaOS4 like previous ROMs worked with previous versions of AmigaOS?

You can boot OS4 from solid-state memory, like a CF card or a ROM, and from things like a USB stick (although not with the current pre-release). The initial hardware init will take some time, though.

[Rogue]

My A1200 would boot to Workbench from a slow 80MB drive in about 6 seconds (I timed it a few times.) That was several years ago. Now, it should boot in less than 4 seconds and maybe even less than 3 seconds.

With nothing on it, yes. Even starting a TCP/IP stack takes longer than that. Of course I can also cut the startup-sequence down to a "LoadWB", but face it, that doesn't turn up anything useful.

That's not my point. It doesn't matter if the OS is stable or not. The desired solution is a system ready to use fast. Today's memory speeds are faster than those in the 80's. So the boot speeds should be faster today as a result.

Quite the contrary. Peolpe come to expect more from their OS than a few years back. If I turn on my machine, I expect it to load the TCP stack, start AmiDock, load a few fonts (with anti-aliasing) and a fancy backdrop for Workbench. Life isn't four color solid-grey workbench anymore. In the same amount that people's expectations grow, the boot time will grow.

What are some ROM solutions in which this can be done using AmigaOS4 (or any other OS)?

ROM solutions for AmigaOS 4 (for the classic) will prevent you from the required re-boot when you switch on your machine by putting the new kickstart modules into a flash rom.

[Rogue]

The network initialization slows it down somewhat,

You can speed it up a bit but adding a "run" in front of AddNetInterface.