Folks,
Sorry for diving in here, but at present there have been essentially
three/four suggestions offered for what hardware might be used:
1) Legacy Apple PowerMac G3/G4 hardware. Someone pointed out the price
of
Pros: -Least expensive hardware by significant margin. Cheap and
plentiful, and likely to only become cheaper.
-Apple no longer cares about PPC hardware.
-"Sawtooth" G4 desktops are plentiful and were manufactured
for
many, many years, due to limitations of clock speed. This is good for
us.
-Motherboard chipset supports up to 2GB RAM.
-OpenFirmware based already. No hackery required. I can only
see
this as a major plus.
-Most-closely resembles modern PowerPC CPU architecture,
supports
AltiVec SIMD extensions.
-Relatively easy availability. I've offered to help
facilitate
anyone on earth to get a used unit who would like one. PowerMac G4's
routinely sell for under $300, often for as little as $85 (see San
Francisco Bay Area Craigslist postings if you don't believe me).
-Despite claims to the contrary, good reference code is
available
for the hardware from other license-compatible sources, namely NetBSD.
Cons: -Various hardware/chipset configurations, although most/all of
these seem to be covered/supported by NetBSD
-Slower, older hardware.
The AGP G4 PowerMac is quickly becoming obsolete in the eyes of most
mac users. Speeds for this line of Macs range from 350MHz up to
450MHz, with third-party drop-in PPC CPU upgrades also available used
at a low cost.
The AGP G4 Tower (of?) PowerMac is based on/uses the PowerPC 7400. For
an architectural overview of some of the specifics of the 7400, visit
http://arstechnica.com/articles/paedia/cpu/ppc-2.ars/2
. Here's a brief excerpt:
"The new AltiVec instructions, which I've covered in detail in
elsewhere, were first introduced in the 7400. The 7400 executes these
instructions in its vector unit, which consists of two vector
execution units: the vector ALU (VALU) and the vector permute unit
(VPU). The VALU performs vector arithmetic and logical operations,
while the VPU performs permute and shift operations on vectors. To
support the AltiVec instructions, which can operate on up to 128 bits
of data at a time, 32 new 128-bit vector registers were added to the
PowerPC ISA."
The final PPC product apple ever sold, the G4-based Mac Mini, still
costs a fair bit, around $499. The Tower G4's, however, can be had for
a song: MegaMacs.com sells 30-day-warranty, refurbished PowerMac G4
450 Mhz 256MB/20GB/DVD boxes for $180 USD + $50 USD for shipping to
the US48. http://tinyurl.com/3bbq2q
For more detailed technical information on this line of CPUs, please
visit http://en.wikipedia.org/wiki/PowerPC_G4
2) Playstation3 -Cell Broadband Engine based PPC.
Pros: -Lots of bang for the buck, horsepower wise.
-Has embedded gigabit ethernet.
Cons: -Not a ton of RAM (256MB XDR Main RAM @3.2GHz ), non-user
upgradable.
-Not OpenFirmware based
-Hypervisor would take lots of coding man-hours to
program around/
with, and would be non-portable.
-Sony not likely to support this endeavour
wholeheartedly
-Lack of some hardware documentation, although IBM
provides some
-No NetBSD port to borrow code from, Linux port works
(I have it
installed on mine) but code is off-limits.
3) Dedicated POWER6 hardware and/or Freescale-type PPC devkit:
Not sure what a POWER6 machine would cost, but I know the Freescale
PPC eval board is $4,000 USD.
-So expensive it would likely require corporate backing
-Severely limits ability of potential contributors to
test on local
hardware
-IBMs lowest-end 1-way POWER5-based server costs
$7,995.00 for
1.9GHz with 1GB RAM, although it's amazing that the CPU on the POWER5
line has a whopping 36MB L3 cache.
On Mar 16, 2008, at 12:53 PM, Cyril Plisko wrote:
> On Sun, Mar 16, 2008 at 7:17 PM, Dennis Clarke
> <dclarke at blastwave.org> wrote:
>>
>> Many lessons have been learned over the past three years and we
>> have a
>> platform upon which to stand. This is not just hot air with a
>> slide show on a projector. If we are to go forwards then I think we
>> need to
>> engage IBM people and look at the POWER6. If we are to simply
>> continue
>
> +1
>
> IMO, without strong corporate backing the project won't go anywhere.
>
> --
> Regards,
> Cyril
> _______________________________________________
> powerpc-discuss mailing list
> powerpc-discuss at opensolaris.org
