[OMPI devel] RFC: Adding -DOPEN_MPI=1 to mpif77 and mpif90

2010-02-10 Thread Jeff Squyres
WHAT: Add -DOPEN_MPI=1 to the mpif77 and mpif90 command lines WHY: Parity with mpi.h's "#define OPEN_MPI 1" WHERE: ompi/config/ompi_setup_wrappers.m4 WHEN: v1.5.1 TIMEOUT: Friday, Feb 19 We've long-since had "#define OPEN_MPI 1" in mpi.h for anyone

Re: [OMPI devel] failure with zero-length Reduce()andbothsbuf=rbuf=NULL

2010-02-10 Thread George Bosilca
In not throwing my $.02 cent on this discussion ;) On Feb 10, 2010, at 12:50 , Lisandro Dalcin wrote: > PS: The following question is unrelated to this thread, but my > curiosity+laziness cannot resist... Does Open MPI has some MCA > parameter to add a synchronization at every collective call? Y

Re: [OMPI devel] failure with zero-length Reduce()andbothsbuf=rbuf=NULL

2010-02-10 Thread Lisandro Dalcin
On 10 February 2010 14:19, Jeff Squyres wrote: > On Feb 10, 2010, at 11:59 AM, Lisandro Dalcin wrote: > >> > If I remember correctly, the HPCC pingpong test synchronizes occasionally >> > by >> > having one process send a zero-byte broadcast to all other processes. >> >  What's a zero-byte broadc

Re: [OMPI devel] failure with zero-length Reduce()andbothsbuf=rbuf=NULL

2010-02-10 Thread Jeff Squyres
On Feb 10, 2010, at 11:59 AM, Lisandro Dalcin wrote: > > If I remember correctly, the HPCC pingpong test synchronizes occasionally by > > having one process send a zero-byte broadcast to all other processes. > > What's a zero-byte broadcast? Well, some MPIs apparently send no data, but > > do ha

Re: [OMPI devel] failure with zero-length Reduce() andbothsbuf=rbuf=NULL

2010-02-10 Thread Lisandro Dalcin
On 10 February 2010 13:42, Eugene Loh wrote: > Here is a related case. > > If I remember correctly, the HPCC pingpong test synchronizes occasionally by > having one process send a zero-byte broadcast to all other processes. >  What's a zero-byte broadcast?  Well, some MPIs apparently send no data,

Re: [OMPI devel] failure with zero-length Reduce() andbothsbuf=rbuf=NULL

2010-02-10 Thread Lisandro Dalcin
On 10 February 2010 11:48, Jeff Squyres wrote: > On Feb 10, 2010, at 8:40 AM, Lisandro Dalcín wrote: > >> > Note that from a standards perspective, note that MPI_REDUCE *does* >> > require at least one element -- MPI-2.2 p163:34-35: >> > >> >   "Each process can provide one element, or a sequence

Re: [OMPI devel] failure with zero-length Reduce() andbothsbuf=rbuf=NULL

2010-02-10 Thread Eugene Loh
Here is a related case. If I remember correctly, the HPCC pingpong test synchronizes occasionally by having one process send a zero-byte broadcast to all other processes. What's a zero-byte broadcast? Well, some MPIs apparently send no data, but do have synchronization semantics. (No non-r

Re: [OMPI devel] failure with zero-length Reduce() andbothsbuf=rbuf=NULL

2010-02-10 Thread Jeff Squyres
On Feb 10, 2010, at 8:40 AM, Lisandro Dalcín wrote: > > Note that from a standards perspective, note that MPI_REDUCE *does* require > > at least one element -- MPI-2.2 p163:34-35: > > > > "Each process can provide one element, or a sequence of elements..." > > Are you really convinced that suc

Re: [OMPI devel] failure with zero-length Reduce() and bothsbuf=rbuf=NULL

2010-02-10 Thread Lisandro Dalcín
On 10 February 2010 09:31, Jeff Squyres wrote: > Thanks for the reminder. > > Note that from a standards perspective, note that MPI_REDUCE *does* require > at least one element -- MPI-2.2 p163:34-35: > >   "Each process can provide one element, or a sequence of elements..." > Are you really conv

Re: [OMPI devel] failure with zero-length Reduce() and bothsbuf=rbuf=NULL

2010-02-10 Thread Jeff Squyres
Thanks for the reminder. Note that from a standards perspective, note that MPI_REDUCE *does* require at least one element -- MPI-2.2 p163:34-35: "Each process can provide one element, or a sequence of elements..." So I think that George's assertion is correct: your test code is incorrect. B