Re: Bug#961108: openmpi: providing 64-bit MPI

[Alastair McKinstry <alastair.mckinstry@sceal.ie>]

On 20/05/2020 10:07, Gard Spreemann wrote:
> Drew Parsons <dparsons@debian.org> writes:
>
>> If I understand correctly, it's dangerous to simply enable 64-bit in
>> PETSc alone. It needs to be done all along the computational library
>> stack.

In the case of openmpi, I've just done an experimental 64-bit build,
4.0.3-7 and uploaded to test if it builds correctly on all architectures.

I'd be in favour of 64-bit computational stacks; some of the packages
(pnetcdf, etc) already don't work with 32-bit; It should make is
_possible_ to run on 32-bit,

but accept that performance on 64-bit counts for our users. Taking a
perf hit on 32-bit archs to make 64-bit archs faster is reasonable;

the question becomes - can 32-bit archs handle 64-bit code (int64 etc),
or are we dropping support for 32-bit archs ?

>  
>
-- 
Alastair McKinstry, email: alastair@sceal.ie, matrix: @alastair:sceal.ie, phone: 087-6847928
Green Party Councillor, Galway County Council