[gmx-developers] thread problem on AMD 12 core chips?

[David van der Spoel]

On 2012-01-12 11:36, Berk Hess wrote:
> On 01/12/2012 11:24 AM, David van der Spoel wrote:
>> On 2012-01-12 11:17, Berk Hess wrote:
>>> Which compiler is this?
>>> We get lots of warnings with gcc4.6, but we run regularly on 32 and 64
>>> core nodes.
>>
>> Thread model: posix
>> gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5)
>>
>> Is intel more reliable?
> This is not a matter of platform I would think.
> We have only used AMD platform with 32 or more MPI threads.
> I would guess this is a thread-mpi bug or a compiler issue.
Compiling with Intel C 12.0.3.174 gives the same error, but the same 
pthread library is linked in.

Other tips for debugging this?

>
> Berk
>>>
>>> Berk
>>>
>>> On 01/12/2012 11:04 AM, David van der Spoel wrote:
>>>> Hi,
>>>>
>>>> I'm trying to compile and install gromacs release-4-5-patches on a new
>>>> cluster with four 12-core AMD chips (abisko in Umea, Sweden). However
>>>> the threaded code bails out with the following message:
>>>>
>>>> Reading file topol.tpr, VERSION 4.5.5-dev-20120111-9181e (double
>>>> precision)
>>>> Starting 32 threads
>>>> tMPI error: tMPI Initialization error (in valid comm)
>>>>
>>>> First, I'm a bit confused why the code detects only 32 cores, second
>>>> it shows above error and quits.
>>>>
>>>> Any clues?
>>>
>>
>>
>


-- 
David van der Spoel, Ph.D., Professor of Biology
Dept. of Cell & Molec. Biol., Uppsala University.
Box 596, 75124 Uppsala, Sweden. Phone:	+46184714205.
spoel at xray.bmc.uu.se    http://folding.bmc.uu.se