

The world's slowest Linux PC - kudu
http://www.extremetech.com/extreme/124287-the-worlds-slowest-linux-pc

======
stragulus
This reminds me of the dial-in server I built in our student home back in
'97-'98\. It was a 386sx 16Mhz with 2MB of memory and a 40MB hard drive that
you had to preheat in the oven or it wouldn't spin up. That was realistically
the lowest spec'd hardware you could actually get to run linux on.

It took half an hour to boot, but that was okay since it was always on anyway.
It took about 5 minutes to set up a ppp connection using a dial-in modem, and
then the whole house had internet access through its network adapter. Unless
someone had tripped over the coax cables again of course..

~~~
pjmlp
I had one when they were pretty new, back in 1991.

Had MS-DOS reduced to the minimum, jumping into Windows 3.1 straight after
booting and using Stacker to be able to double the hard disc contents.

By the time I came to use GNU/Linux, I was already on Pentium 75 Mhz and never
imagine such 386sx would ever manage it.

------
voltagex_
Previously:
[https://news.ycombinator.com/item?id=8791812](https://news.ycombinator.com/item?id=8791812),
[https://news.ycombinator.com/item?id=5581851](https://news.ycombinator.com/item?id=5581851)

~~~
jared314
More Previously:

[https://news.ycombinator.com/item?id=3767410](https://news.ycombinator.com/item?id=3767410)
(1054 days ago)

~~~
voltagex_
Thanks. I wonder if I can automate that - although HN bans bots, right?

~~~
jared314
Just add it to one of the many HN browser extensions.

The tough part is correlating the different urls and titles while filtering
out the irrelevant comments from past discussions. I don't just want to know
that this is an old story (I can figure that out), or that it's a "cool
project" that a commenter might use sometime soon, 5 years ago.

I want to know what the informed comments were at that time. Was it important
in that time period? What were the concerns at the time? Did they abandon the
idea? Why?

------
jrockway
"Calibrating delay loop... 58.77 BogoMIPS"

As a comparison, from my i7-4771 @ 3.5GHz:

smpboot: Total of 8 processors activated (55999.93 BogoMIPS)

Computers sure are fast these days. Too bad we write such slow software for
them.

~~~
iso8859-1
Except if you emulate them in JavaScript. I get 5.10 BogoMIPS:
[http://copy.sh/v86/?profile=custom&cdrom.url=http://k%C3%A6n...](http://copy.sh/v86/?profile=custom&cdrom.url=http://k%C3%A6n.guru/files/ttylinux-
pc_i486-2015.01.iso)

~~~
Maakuth
The bogomips is a really bad estimate of performance (hence 'bogo'). There's
considerable difference in the bogomips calculation even between different ARM
subarchitectures. There was a good article about the issue recently in LWN:
[http://lwn.net/Articles/628531/](http://lwn.net/Articles/628531/)

------
elinchrome
How do you emulate a 32 bit CPU with only eight bits? Seems like you'd have to
quadruple everything and then flatten it again after.

~~~
danbruc
This is actually pretty common. There was a time when not every CPU had a FPU
and floating point operations were emulated in software if required. Or doing
64 bit integer operations on a 32 bit CPU. Or doing arbitrary precision
arithmetics on todays CPUs. You do it just like in school, piece by piece, but
instead of single digits you use the largest registers available. If you
really like it slow you could of course also just use plain strings to
represent numbers and do all math on a char by char, digit by digit basis.

------
ChuckMcM
While I agree it is not novel at all [1] it is a useful exercise for someone
to do and it especially reinforces the notion that Turing discussed with
respect to computability. For a long time (and possibly even today) every IBM
mainframe could emulate (at speed or faster) all previous versions of their
mainframe line such that the investment in software was preserved.

[1] I did a PDP-11 emulator on the Arduino with FRAM chips for 'core' which
was made quite a bit easier by the existence of PDP-11 instruction set
diagnostics, and other test software which validated the CPU was running
"correctly".

------
swatow
Somehow the fact that this was accomplished by emulating a 32 bit processor
with an 8 bit processor, made this less appealing to me. I'm sure it was
technically very challenging, but I would have been more excited to see Linux
somehow running natively on the processor. I wonder what the slowest
processors running Linux natively are?

~~~
JoshTriplett
For x86, older versions of Linux ran on a 386, but current versions require a
486, or a Pentium if you turn on stack protection (as most distro kernels do).
(Almost nobody noticed.) However, drivers for ISA and similar still exist in
the kernel, so you could likely get the most recent kernel running on a real
486, if you had one around.

The slowest systems still running Linux, though, are probably those running
the m68k port. Many people doing development for that port use m68k emulators,
which run many times faster than the fastest available hardware. However, at
least in theory, you can run the m68k port on any m68k processor that has an
MMU.

~~~
ansible
And you can run uCLinux on the m68k processors that don't have an MMU. I was
using it for a Motorola Dragonball microcontroller... 14 years ago.

------
parski
How I would dread debugging this machine.

~~~
ansible
The main thing is to get the ARM instructions working correctly, so that's not
too bad. If all of those are correct, it should boot and do basic stuff. The
next bit of work is to get the peripherals going.

------
boyter
Interesting, but I found this effort
[http://www.homebrewcpu.com/](http://www.homebrewcpu.com/) more impressive
overall. It quite literally is a home made CPU which then had Minix 2 ported
to it and booted. A very impressive achievement.

~~~
code_duck
Neat article! I love the box he put it in. The neatly labeled sections are
somewhat fascinating and give interesting insight into how a CPU works. Things
seem different when your CPU is a foot long and sits on the table I suppose...

