On Thu, 21 Oct 2021 21:02:45 +0100
Post by James HarrisYou guys might be interested in this. The guy claims it as the
world's fastest-booting PC. That may be something of an overclaim but
this is the fastest I've ever seen a PC boot - about 2.5 seconds to
MS-DOS 3.3. And that's on an 8086!
http://youtu.be/DaSkda4XW3k
Didn't you bring up this issue previously? Or, was that someone else?
Well, that is for an early small BIOS, with a very small text-based OS,
probably without any device drivers, with a relatively fast for the era
8086. Yes? And, it really didn't seem like it was loaded from a
floppy (real slow) or MFM hard disk (slow). So, I suspect it would've
been much slower if it was. Didn't he say something about a ROM drive?
Well, this mostly 2009 parts computer, i.e., a decade or so old now
(assembled 2013), takes roughly six seconds to boot MS-DOS 7.10, from a
slow Compact Flash card which is probably comparable to a hard disk, or
maybe slower ... Two seconds for the BIOS to execute, with most of that
time spent dynamically identifying hardware upon boot. Some uncounted
time for me to manually to select from the boot menu the DOS drive to
boot from, as it's non-primary. Then, about four seconds to load
MS-DOS and some DOS drivers. Obviously, it would be faster without the
drivers, if the machine booted straight through to the DOS drive, and
if I still had DOS on the SSD instead of the CF card. My recollection
was that it was nearly instantaneous to boot DOS when it was on the
SSD, taking only time for the BIOS to identify hardware.
So, your definition of "boot" doesn't only include executing the BIOS
and transferring execution to the boot loader? I.e., you define "boot"
as including executing the BIOS/UEFI, executing the boot loader (etc)
too, and executing a small text OS too, but not executing a large GUI
OS.
Since this machine is old now, I'd think that newer machines could boot
DOS just as fast, assuming they can even still boot DOS, and perhaps
even boot Linux or Windows GUIs quickly too.
Linux wastes lots of time displaying text of what it's doing when
booting/loading. It doesn't take that long, just a few seconds, to
start Linux GUI (XFCE) from a text-mode, command-line boot of Linux, on
this old machine. I wouldn't doubt it if Linux could be make to boot
into the GUI in about five seconds, if all the text display from Linux
boot scripts was deleted. BIOS 2 secs, Linux OS 1 sec (normally about
20 to 30 seconds ...), GUI 2 secs.
Windows 10, when it is being booted cleanly, wastes lots of time doing
something too, which I suspect is re-identifying hardware and
re-configuring. I suspect that because powered down or unplugged USB
devices are fairly consistently lost, or fail to be re-found correctly
once re-plugged or re-powered, sometimes requiring booting into
safe-mode to restore all of them.
I agree that booting/loading could be faster, but then you'd need to do
some sort of save-state of the OS, like certain OSes do when the
computer "sleeps" or "hibernates" or does a "quick shutdown". You'd
also need some way to quickly reset the hardware to the correct states
to match that of the OS save-state. And, if the OS boots fast, because
the machine is fast, what's the point?
--
Donald Trump: No oil rigs off the East coast.
Joe Biden: Windfarms off of all our coasts.