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Re: New architecture ppc64el on Debian

I suppose I'm not really one privileged to express these reactions,
but I tend to be a loose cannon sometimes.

On Sun, Sep 22, 2013 at 2:42 AM, Breno Leitao <brenohl@br.ibm.com> wrote:
> Hi,
> Now that PowerPC was announced to have Little Endian support, I'd like to enable
> it on Debian, as a ppc64el architecture.


(Checking my calendar. Nope, I haven't suddenly slipped back to the
early 1990s.)

(Still puzzled.)

> I have been working internally at IBM on a Debian rootfs that runs on this
> architecture. As a plan, I am looking, in general, to have this architecture
> included on sid, first, and then being moving towards stable.

So, pardon me for being dense, but is the build process really going
to be all that much more difficult than putting a compiler flag for
least significant byte first in the make files and typing make?

I suppose, along with lsb-first, there are some changes in the soc
peripherals and some special tuning of the instruction set. I'm
assuming the latter is taken care of by the compiler, which I assume
you already have had running and debugged for the newly tuned parts
for at least a few months?

Not that it's my problem to worry about at all.

> Unfortunately the process is still in the beginning and we will not have a machine
> for public access in the near term, although, this is one of our targets, as
> having two other buildd machines in different locations to support autobuilder.

My impression is that the sooner you can have the new target hardware
available to donate to the build farms the better, as someone else has
also mentioned.

And I'm wondering if this "little-endian" hardware is hardwired
"little-endian", and why the fuss?

> Should I take any concern before start submitting patches to enable this architecture?

You've had several people hint. I've hinted, too. It seems like there
is something that needs to be explained.

Why the fuss?

It's not like endian-ness is a barrier to performance. Is there some
Intel-fomented rumor floating around data centers with BOFH admins,
that the endian-ness is the Power architecture's Achilles' heel or

Hmm. I suppose it might have something to do with graphics chips which
seem to be all x86-oriented and are now being used as dedicated
numeric array processors, per this commentary in LWN:
<http://lwn.net/Articles/408845/>. That's going the way of the dodo in
about three to five years, but I suppose there may be some purpose in
reactionary marketing now.

Well, anyway, the devs are the ones to make up their minds on how much
resource to put in on this, so I suppose I should shut up. But it sure
seems like Intel leads a lot of useless market churn. If the
predictions about global climate change turn out to be true, when the
amount of excess waste heat generated by using x86 in infrastructure
is calculated, do we sue Intel for the part it plays in wasting the
earth through excess hardware turnover and energy use?

> Thanks
> Breno
> --
> Breno Leitão
> Linux Technology Center
> Phone: +55 16 8115-3915

Joel Rees

Be careful where you see conspiracy.
Look first in your own heart.

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