[MPICH] RE:Multithreading bugs

[Rajeev Thakur]

The bug-tracking system we use isn't publicly accessible. In the 1.0.3
release, there aren't any known problems with multithreading support.

Rajeev 


> -----Original Message-----
> From: owner-mpich-discuss at mcs.anl.gov 
> [mailto:owner-mpich-discuss at mcs.anl.gov] On Behalf Of David Minor
> Sent: Monday, December 19, 2005 12:45 AM
> To: Ralph M. Butler
> Cc: mpich-discuss at mcs.anl.gov
> Subject: [MPICH] RE:Multithreading bugs
> 
> Hello Ralph,
> You mention here problems with multi-threading support. Is 
> there a central bug base I can browse to look at known bugs 
> and problems with the mt support?
> 
> David Minor
> Orbotech 
> 
> -----Original Message-----
> From: owner-mpich-discuss at mcs.anl.gov 
> [mailto:owner-mpich-discuss at mcs.anl.gov] On Behalf Of Ralph M. Butler
> Sent: Saturday, December 17, 2005 6:05 PM
> To: Koehne Kai
> Cc: mpich-discuss at mcs.anl.gov
> Subject: Re: [MPICH] MPLMD (Multiple Programming Languages 
> Multiple Data)
> 
> Perhaps I should not comment since I cannot address your main 
> problem with Java, but I will toss in 2 cents anyway.  I 
> occassionally develop code in which a single app uses a 
> combination of Python and C.  Just last week I wrote one on 
> linux which has multiple P-threads (as servers) in a C 
> program that uses MPI_Send/Recv on 3 different communicators.
> The Python portions of the app have access to the MPI 
> functions as well.
> I am still coding/debugging that app, but believe that 
> everything is going to be OK.  My major concern going into 
> this particular app was that I would encounter bugs in the 
> MPICH multi-threading support since that is still relatively 
> new.  But, so far things have gone fine.
> 
> A couple of years ago I examined some of the open Python 
> wrappers for MPI, but found that they were never quite what I 
> wanted.  So, I just roll my own whenever I need something.  I 
> generally send Python objects as pickled objects that can 
> travel as byte strings.
> So, in Python, I can do something like this:
>     pickledMsg = cPickle.dumps(obj)
>     mympi.Send(pickledMsg,toRank,tag)
> 
> Here is a sample wrapper to support that:
> 
> static PyObject *Send(PyObject *self, PyObject *pArgs) {
>     int msglen,torank,tag;
>     char *msg;
> 
>     if ( ! PyArg_ParseTuple(pArgs,"s#ii",&msg,&msglen,&torank,&tag))
>     {
> 	printf("Send: invalid args\n");
> 	return NULL;
>     }
>     MPI_Send(msg,msglen,MPI_BYTE,torank,tag,MPI_COMM_WORLD);
>     return Py_BuildValue("");  /* None */ }
> 
> --ralph
> 
> > Date: Sat, 17 Dec 2005 10:28:57 +0100
> > From: Koehne Kai <Kai.Koehne at student.hpi.uni-potsdam.de>
> > To: mpich-discuss at mcs.anl.gov
> > Subject: [MPICH] MPLMD (Multiple Programming Languages 
> Multiple Data)
> >
> > Hello,
> >
> > first of all sorry if the question sounds stupid to you, or 
> if this is not the right place to ask. I am pretty new to MPI 
> in general, and could not find a more specific discussion board ...
> >
> > The Multiple Programs Multiple Data (MPMD) paradigm is 
> pretty well documented for MPICH. However, I am trying to let 
> multiple programs, written in different programming languages 
> (Java and Python), to communicate. I tried to achieve that 
> with two MPI wrapper libraries, namely mpiJava and pypar.
> >
> > However, I failed: When combining small Python and Java 
> demo programs in one MPICH procgroup file, the Java programs 
> seem to hang up in the MPI initialization call.
> >
> > It might be that this problem is specific to the mpiJava 
> wrapper implementation. However, I am a bit astonished that 
> the whole idea of combining MPI programs from different 
> programming languages is hardly ever explained in the 
> literature. Have you had experience with such a setting? And 
> can you recommend me a specific Java wrapper implementation 
> that is known to communicate nicely with other wrapper 
> implementations?
> >
> > Regards,
> >
> > Kai Koehne
> > Hasso-Plattner-Instute
> > University of Potsdam
> > Germany
> >
> >
> >
> 
>