Tuesday, February 24th, 2015

	Previously prepared positions
	~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

During the last years of WWII, when soviet army was pushing Germans
back from east to west, German propaganda was calling every defeat
as "withdraw to the previously prepared positions". They were 
withdrawing and withdrawing until they were back in Berlin and the
war was over. During the last weekend, my fight with systemd on 
took the very same turn, at least on 64-bit PowerPC.

If you have 64-bit PowerPC machine, you don't have many options,
especially if you want system without systemd: Crux PPC Linux, Gentoo
Linux and FreeBSD. As Crux PPC hasn't been updated since 2013, the
list is reduced to two current operating systems. I tried them both.

Gentoo Linux
You probably know it, but in this distro you have to build everything
from the source code. I'm patient enough to do this, so that wouldn't
be major problem. What is a problem, is the nonfunctional thermal
management during install and initial kernel build process. PM G5 is
really noisy when it has all fans on maximum and I simply can't have
all fans on maximum for two or more days, because I have to live near
the machine with my family. Maybe I could cross-compile the kernel on
a x86 machine or set up emulated PPC64 machine and build kernel
there, transfer the result to PM G5 and with that new kernel do the
rest of the build, but that sounds like something you would do only
as the last remaining option.

FreeBSD
If you decide to leave the Linux family, there is just one option.
Neither OpenBSD nor NetBSD support PPC64, so if you don't want to use
your hardware in 32bit mode with just 2GB of RAM, you have no other
choice than FreeBSD. In FreeBSD thermal management kind of works, but
as you probably guessed from "kind of" it's far from being perfect.
Both CPUs are underclocked to 1300MHz and if you look at sysctl
output, you see weird values in fan speeds and sensor values. The 
only fan that seems to be changing rpm value is "backside" and I
seriously doubt that the whole machine can be cooled properly just by
changing speed of a single fan. As both CPUs are underclocked, I took
the risk and installed the system. PowerPC port is in Tier 2, which
means that there are no official binary packages and you have to 
build everything yourself, much like in the Gentoo Linux. I tried 
building few simple utilities to see what machine would do under load
and as it seemed alright, I started to build X.org. It took almost
20 hours with all dependencies and I saw couple of overheating 
reports in the console, but "backside" fan always managed to cool
the hot U3 chipset down.

So now I have FreeBSD on my PowerMac G5 as well as Mac OS X 10.5.8.
I subscribed to the freebsd-ppc mailing list and asked few questions
about the thermal management and CPU clocking and if I receive some
useful answers, FreeBSD stays. Otherwise I will have to withdraw to
the previously prepared positions or in another words to acknowledge
my defeat and return back to Debian with all that systemd plague.

One way or another, this makes item 2 from my New Year's to-do list
complete. Six more to go!

.