Fedora 22

[Peter Robinson]

>>> >>   We briefly discussed priorities for Fedora 22 and I had taken an
>>> >> action item to start an email conversation about this.  So here is
>>> >> what I would like to see for Fedora 22.
>>> >>
>>> >> 1)  Get the -mcpu and -mtune flags set properly for the LE build.
>>> >> Should be -mcpu=power7 -mtune=power8
>>> >
>>> > done, all packages that honour the Fedora system wide compiler flags
>>> > use them, if they don't it's a packaging bug
>>> >
>>> >> 2) Have a cloud image available
>>> >> 3) For BE I would like another subarch.  Same packages as the current
>>> >> one but tuned for P8.
>>> >
>>> > you mean in addition to ppc64p7? can't we just switch ppc64p7 from
>>> > -mcpu=power7 -mtune=power7 to -mcpu=power7 -mtune=power8?
>>>
>>> This makes sense to me as it then mirrors what we have in ppc64le and
>>> it saves having more targets.
>>
>> The disadvantage of this would be to cut off users that have Power 7 systems
>> and optimized code.  So why would people want to optimize from Fedora 21 to
>> Fedora 22.  You would be taking a big step back in performance.  I don't
>> want to suggest keeping a subarch for each type of POWER system out
>> there.  I
>> was thinking of keeping two.  So when the next POWER arch that comes out,
>> the Power 7 subarch goes away and you would have Power 8 and the new
>> Power arch.
>
> That would mean that enthusiasts like myself, happily running Fedora on
> a Power 285 workstation, would lose Fedora?

No, there's a sub arch called ppc64p7 which provides optimised
binaries for a sub set of packages which has been a feature for a few
releases and is what is being discussed with the terms "For BE I would
like another subarch"

> I'd really like to keep it. Red Hat dropped Power5 support quite a time
> ago, so if there ever comes a CentOS 7 ppc to life, it'd had to be
> tweaked to run on those machines. *If*, that is. Furthermore, Power6
> boxes aren't that old, either.

If there ever was a CentOS7 option for POWER I suspect they would take
the same options for RHEL, and POWER6 dates back to 06/07 so define
old.

> I just want to emphasize that with keeping "old" metal running (we're
> not talking of ancient hardware) the useable hardware available for
> people doing this on a hobbyists scale would be much bigger -- so would
> be the community. Having Power 7 and Power 8 only, that wouldn't be the
> case any longer.

We're not dropping it, we're adjusting the ppc64p7 sub architecture
for newer stuff, and that sub architecture was always POWER7 it's
actually just adjusting the processors we optimise for. There is no
change.

Peter