[gmx-users] Can't run v. 4.6.6 on worker nodes if they are compiled with SIMD

Seyyed Mohtadin Hashemi haadah at gmail.com
Sat Jul 26 19:35:04 CEST 2014


On Jul 26, 2014 4:52 AM, "Mark Abraham" <mark.j.abraham at gmail.com> wrote:
>
> Hi,
>
> That is indeed very weird - particularly if compiling on the compute nodes
> with GPU support enabled gives the same result. Both host and compute
nodes
> support rdtscp, so that known suspect is OK. I can only guess that there's
> something in the CUDA installation process that targets the CPU on the
> install host. Configuring with -DCMAKE_BUILD_TYPE=Debug and getting a
stack
> trace from the crash might help work out where the problem arises.

Will get back with the stack trace a bit later; is "gdb bt full" ok? Or do
you want "thread info" as well?

Doing a
> CUDA install on a compute node and compiling against that might help.

You mean install CUDA SDK on the worker nodes? If so, this is already done
and gives same result. I will ask the admin about the configuration of CUDA
on the worker nodes.
>
> Mark
>
>
>
> On Fri, Jul 25, 2014 at 10:00 PM, Seyyed Mohtadin Hashemi <
haadah at gmail.com>
> wrote:
>
> > Hi everyone,
> >
> > I'm having a very weird problem with GROMACS 4.6.6:
> >
> > I am currently testing out GPU capabilities and was trying to compile
> > GROMACS with CUDA (v6.0). I can not make this work if I compile GROMACS
> > with SIMD, no matter what kernel I choose - I have tried everything from
> > SSE2 to AVX_256.
> >
> > The log-in node, where I compile, has AMD Interlagos CPUs (worker nodes
use
> > Xeon E5-2630 and are equipped with Tesla K20), but I do not think this
is
> > the problem - I have compiled GROMACS, using the log-in node, without
CUDA
> > but with AVX_256 SIMD and everything works. As soon as CUDA is added to
the
> > mix, I get "Illegal Instruction" every time I try to run on the worker
> > nodes.
> >
> > Compiling on worker nodes gives the same result. However, as soon as I
set
> > SIMD=None everything works and I am able to run simulation using GPUs,
this
> > is regardless of if I use log-in node or worker node to compile.
> >
> >
> > The cmake string used to configure is:
> > ccmake .. -DCMAKE_INSTALL_PREFIX=/work/gromacs4gpu -DGMX_DOUBLE=OFF
> > -DGMX_DEFAULT_SUFFIX=OFF -DGMX_BINARY_SUFFIX=_4gpu
-DGMX_LIBS_SUFFIX=_4gpu
> > -DGMX_GPU=ON -DBUILD_SHARED_LIBS=OFF -DGMX_PREFER_STATIC_LIBS=ON
> > -GMX_MPI=OFF -DGMX_CPU_ACCELERATION=AVX_256
> >
> > CUDA v6.0 and FFTW v3.3.4 (single precision) libs are set globally and
> > correctly identified by GROMACS. To remove OpenMPI as a problem I am
> > compiling without it (compiling with OpenMPI produced the same behavior
as
> > without), once I have found the error I will compile with OpenMPI
v1.6.5.
> >
> > I get these warnings during the configuration, nothing important:
> >
> >  A BLAS library was not found by CMake in the paths available to it.
> > Falling back on the GROMACS internal version of the BLAS library
instead.
> > This is fine for normal usage.
> >
> >  A LAPACK library was not found by CMake in the paths available to it.
> > Falling back on the GROMACS internal version of the LAPACK library
instead.
> > This is fine for normal usage.
> >
> > I am currently trying to compile and test GROMACS 5.0 to see if it also
> > exhibits the same behavior.
> >
> > I hope that someone can point me in the direction of a possible
solution,
> > if not then I will file a bug report.
> >
> > Regards,
> > Mohtadin
> > --
> > Gromacs Users mailing list
> >
> > * Please search the archive at
> > http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before
> > posting!
> >
> > * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists
> >
> > * For (un)subscribe requests visit
> > https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or
> > send a mail to gmx-users-request at gromacs.org.
> >
> --
> Gromacs Users mailing list
>
> * Please search the archive at
http://www.gromacs.org/Support/Mailing_Lists/GMX-Users_List before posting!
>
> * Can't post? Read http://www.gromacs.org/Support/Mailing_Lists
>
> * For (un)subscribe requests visit
> https://maillist.sys.kth.se/mailman/listinfo/gromacs.org_gmx-users or
send a mail to gmx-users-request at gromacs.org.


More information about the gromacs.org_gmx-users mailing list