From: "Rolf Rabenseifner" Date: January 28, 2008 2:24:32 AM CST To: "Mailing list for discussion of MPI 2.1" Subject: Re: [mpi-21] MPI_GET_PROCESSOR_NAME Fortran and C Reply-To: "Mailing list for discussion of MPI 2.1" Dick, your right and it is already decided: MPI 1.1 Sect. 7.1 page 193, lines 13-14: "This routine returns the name of the processor on which it was called at the moment of the call." And lines 22-25: "Rationale. This function allows MPI implementations that do process migration to return the current processor. Note that nothing in MPI requires or defines process migration; this definition of MPI GET PROCESSOR NAME simply allows such an implementation. (End of rationale.)" I.e., current location, i.e., it may change in case of check point/restart and all the other reasons you mentioned. I would say, that the sentences above are clear enough. Okay? Best regards Rolf On Fri, 25 Jan 2008 15:32:07 -0500 Richard Treumann wrote:> We also should decide whether every call to MPI_GET_PROCESSOR_NAME > across > the life of the task must return the same name. On very large > machines > running very large jobs, migration of some tasks off of failing > nodes and > on to robust nodes will become more interesting. Checkpoint/restart > raises > the same issue. A restarted job will probably not have the same > task to > node mapping. > > We can either require the name to remain constant and allow that it > might > be a "virtual" name or require that it return an "actual" name but > allow it > to change. > > Dick > > Dick Treumann - MPI Team/TCEM > IBM Systems & Technology Group > Dept 0lva / MS P963 -- 2455 South Road -- Poughkeepsie, NY 12601 > Tele (845) 433-7846 Fax (845) 433-8363 > > > mpi-21-bounces@XXXXXXXXXXX wrote on 01/25/2008 12:00:42 PM: > >> This is a discussion-point for MPI 2.1, Ballot 4. >> >> This is a follow up to: >> MPI_GET_PROCESSOR_NAME and Fortran >> in http://www.cs.uiuc.edu/homes/wgropp/projects/parallel/MPI/mpi- >> errata/index.html >> with mail discussion in >> http://www.cs.uiuc.edu/homes/wgropp/projects/parallel/MPI/mpi- >> errata/discuss/procname/ >> >> _________________________________________________________________ >> >> MPI_GET_PROCESSOR_NAME and Fortran >> and in C and all MPI_xxxx_GET_NAME routines >> ------------------------------------------- >> >> Summary: Returning strings is defined in MPI_GET_PROCESSOR_NAME >> and MPI_xxxx_GET_NAME quite different. Not all implementations >> are doing the same with zero-filling. And what they do is >> at least with MPI_GET_PROCESSOR_NAME different to what >> the current standard requires. A propose to adapt the standard >> to the common reasonable implementations. >> The very short proposal for clarification can be found at the >> end of this text, see C. Proposal. >> >> A. MPI_GET_PROCESSOR_NAME ... >> B. MPI_COMM_GET_NAME (and other MPI_xxxx_GET_NAME) ... >> C. Proposal: >> ------------ >> >> Add the following sentences to the current interface definitions: >> ------------------ >> In C, a \0 is additionally stored at name[resultlen]. resultlen >> cannot be larger then MPI_MAX_PROCESSOR_NAME-1 >> (or MPI_MAX_OBJECT_NAME-1). In Fortran, name(resultlen+1:) >> is filled with spaces. resultlen cannot be larger then >> MPI_MAX_PROCESSOR_NAME (or MPI_MAX_OBJECT_NAME). >> ------------------ >> >> Typo correction: >> ---------------- >> MPI-1.1 Sect. 7.1, page 193, beginning of line 29 reads >> examine the ouput argument >> But should read (additional t in output) >> examine the output argument >> >> >> Okay? >> _________________________________________________________________ >> >> Best regards >> Rolf >> >> PS: Attached my tests and short protocols >> >> >> >> Dr. Rolf Rabenseifner . . . . . . . . . .. email rabenseifner@XXXXXXX >> High Performance Computing Center (HLRS) . phone ++49(0)711/685-65530 >> University of Stuttgart . . . . . . . . .. fax ++49(0)711 / 685-65832 >> Head of Dpmt Parallel Computing . . . www.hlrs.de/people/rabenseifner >> Nobelstr. 19, D-70550 Stuttgart, Germany . (Office: Allmandring 30) >> [attachment "mpi_get_xxx_name.tar.gz" deleted by Richard >> Treumann/Poughkeepsie/IBM] > _______________________________________________ >> mpi-21 mailing list >> mpi-21@XXXXXXXXXXX >> http://lists.cs.uiuc.edu/mailman/listinfo/mpi-21 Dr. Rolf Rabenseifner . . . . . . . . . .. email rabenseifner@XXXXXXX High Performance Computing Center (HLRS) . phone ++49(0)711/685-65530 University of Stuttgart . . . . . . . . .. fax ++49(0)711 / 685-65832 Head of Dpmt Parallel Computing . . . www.hlrs.de/people/rabenseifner Nobelstr. 19, D-70550 Stuttgart, Germany . (Office: Allmandring 30) _______________________________________________ mpi-21 mailing list mpi-21@XXXXXXXXXXX http://lists.cs.uiuc.edu/mailman/listinfo/mpi-21