Open MPI logo

Hardware Locality Users' Mailing List Archives

  |   Home   |   Support   |   FAQ   |   all Hardware Locality Users mailing list

Subject: Re: [hwloc-users] Problems on SMP with 48 cores
From: Samuel Thibault (samuel.thibault_at_[hidden])
Date: 2012-03-13 08:33:05

Hartmut Kaiser, le Tue 13 Mar 2012 12:46:05 +0100, a écrit :
> Trying to use hwloc on a 48 bit core machine (Windows x64) causes problems,
> though. Any information requests for processing units above number 32 return
> garbage (see also the attached output of 'lstopo -of txt').

Ok, so it didn't magically work.

Unfortunately I have no access to a windows machine with that many
cores, so I could not test >sizeof(unsigned long) cores detection
myself, it's thus not very surprising that it does not work.

> I tried to recompile the library using MSVC which would allow me to debug
> the issue, but after several hours of tweaking I gave up. As it turns out
> the code base is everything but portable, which is really unfortunate for a
> library which is supposed to be cross platform.

I'm afraid to have to answer that MSVC does everything but respecting
standards, even when they are more that 10 years old. The hwloc code
compiles as such on a variety of unix compilers, and we didn't need many
tweaks for that. The mingw toolchain saves a lot of such concerns, so I
can only advise to use it.