[CentOS-devel] CentOS 7 (1503) i686 Beta Architecture

[Johnny Hughes]

On 06/05/2015 03:41 PM, Trevor Hemsley wrote:
> Is it really worth the effort? The last Pentium III was released in 2002
> and you couldn't buy them after 2003 so we're talking about machines
> that are 12 or more years old. The fastest one you could ever buy is
> outperformed by a factor of more than 2 times by each core on my dual
> core 2010 vintage Intel Atom D510.
>

I don't mind the effort of compiling so much as the potential for
massive confusion with 2 packages named the same thing but compiled with
different gcc optimizations, as we would still have to provide the other
packages i686 packages in x86_64 arch for multilib.

But, I do agree that trying to run this on 12 year old machines is is
not going to be easy.  CentOS-7 does not perform well without at least
1.5GB - 2GB of RAM as well.  (The installer does not even work well with
less than 1 GB RAM)

If enough people really want it, I guess it could be done as part of the
AltArch Special Interest Group .. but my initial take is not positive
because of the confusion potential.


> On 05/06/15 21:22, Toni Spets wrote:
>> This would be rather unfortunate as that would also leave out all
>> 32-bit only AMD processors (Athlon XP & co) as well according to
>> Wikipedia where it's said Athlon 64 was the first one to add SSE2 and
>> it can already run the 64-bit CentOS anyway.
>>
>> I'm hoping there is more people that could +1 having support for
>> pre-SSE2 CPUs so it would be seriously considered even though it might
>> need massive rebuild of the multilib packages. EPEL doesn't have
>> multilib yet (right?) so they can still adapt to whatever is going to
>> be done. The packages would run on upstream as well anyway.
>>
>> Taking into account the actual computing power of CPUs, I don't think
>> it's unreasonable to run CentOS 7 on Pentium III or Athlon XP.
>>
>> Thanks for considering.
>>
>> On Fri, Jun 5, 2015 at 9:44 PM, Johnny Hughes <johnny at centos.org
>> <mailto:johnny at centos.org>> wrote:
>>
>>     On 06/05/2015 05:46 AM, Vladimir Stackov wrote:
>>     > Greetings,
>>     >
>>     > currently we are maintaining own CentOS 7 i686 rebuild and I
>>     would like
>>     > to kindly ask you to replace following macros from gcc.spec:
>>     >
>>     > %if 0%{?rhel} >= 7
>>     > %ifarch %{ix86}
>>     >    --with-arch=x86-64 \
>>     > %endif
>>     > %ifarch x86_64
>>     >    --with-arch_32=x86-64 \
>>     > %endif
>>     >
>>     > with that:
>>     >
>>     > %if 0%{?rhel} >= 7
>>     > %ifarch %{ix86}
>>     >         --with-arch=i686 \
>>     > %endif
>>     > %ifarch x86_64
>>     >         --with-arch_32=i686 \
>>     > %endif
>>     >
>>     > x86-64 causes gcc to use extended instruction set for produced
>>     code and
>>     > it's impossible to run CentOS 7 i686 on older systems without SSE2
>>     > instruction because of SIGILL.
>>     > This affects Pentium 3, old VIA CPUs, old Xeons and some others.
>>     >
>>     > Is that possible?
>>     > Thanks!
>>     >
>>
>>     <snip>
>>
>>     I don't think we can do this as I also use the RPMs produced for the
>>     multilib portion of CentOS-7 x86_64 and we want our RPMs to be like
>>     those from upstream for that purpose.
>>
>>     Thanks,
>>     Johnny Hughes
>>
>>


-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 198 bytes
Desc: OpenPGP digital signature
URL: <http://lists.centos.org/pipermail/centos-devel/attachments/20150605/20c60724/attachment.sig>