[OMPI devel] MPI_REAL2 support and Fortran ddt numbering
Hello dear all, with the current numbering in mpif-common.h, the optional ddt MPI_REAL2 will break the binary compatibility of the fortran interface from v1.2 to v1.3 (see r15133). Now apart from MPI_REAL2 being of let's say rather minor importance, the group may feal that the numbering of datatypes is crucial to the end user and the (once agreed upon) allowed binary incompatibility for major version number changes is void. (The most important datatype that this change affects is MPI_DOUBLE_PRECISION: users will need to recompile their code with v1.3...) Please raise Your hand if anybody cares. Thanks, Rainer -- Dipl.-Inf. Rainer Keller http://www.hlrs.de/people/keller High Performance Computing Tel: ++49 (0)711-685 6 5858 Center Stuttgart (HLRS) Fax: ++49 (0)711-685 6 5832 POSTAL:Nobelstrasse 19 email: kel...@hlrs.de ACTUAL:Allmandring 30, R.O.030AIM:rusraink 70550 Stuttgart
Re: [OMPI devel] openib coord teleconf
oops, was this yesterday? If it was today, whats the number? Andrew Jeff Squyres wrote: On Jun 13, 2007, at 3:38 PM, Andrew Friedley wrote: I'd like to call in as some of this applies to UD as well, is that okay? Sounds good. Andrew Jeff Squyres wrote: On Jun 13, 2007, at 2:41 PM, Gleb Natapov wrote: Pasha tells me that the best times for Ishai and him are: - 2000-2030 Israel time - 1300-1300 US Eastern - 1100-1130 US Mountain - 2230-2300 India (Bangalore) Although they could also do the preceding half hour as well. Depends on the date. The closest I can at 20:00 is June 19. Oops! I left out the date -- sorry. I meant to say Monday, June 18th. And I got the US eastern time wrong; that should have been noon, not 1300. 20:00 Israel June 19th is right after the weekly OMPI teleconf; want to do it then? ___ devel mailing list de...@open-mpi.org http://www.open-mpi.org/mailman/listinfo.cgi/devel
Re: [OMPI devel] MPI_REAL2 support and Fortran ddt numbering
Rainer Keller wrote: Hello dear all, with the current numbering in mpif-common.h, the optional ddt MPI_REAL2 will break the binary compatibility of the fortran interface from v1.2 to v1.3 (see r15133). Now apart from MPI_REAL2 being of let's say rather minor importance, the group may feal that the numbering of datatypes is crucial to the end user and the (once agreed upon) allowed binary incompatibility for major version number changes is void. (The most important datatype that this change affects is MPI_DOUBLE_PRECISION: users will need to recompile their code with v1.3...) Please raise Your hand if anybody cares. Sun cares very much about this for the exact reason you state (Binary compatibility). I'd prefer this ddt is placed at the end of the list. thanks, --td
Re: [OMPI devel] MPI_REAL2 support and Fortran ddt numbering
On Jun 19, 2007, at 8:35 AM, Terry D. Dontje wrote: Rainer Keller wrote: Hello dear all, with the current numbering in mpif-common.h, the optional ddt MPI_REAL2 will break the binary compatibility of the fortran interface from v1.2 to v1.3 (see r15133). Now apart from MPI_REAL2 being of let's say rather minor importance, the group may feal that the numbering of datatypes is crucial to the end user and the (once agreed upon) allowed binary incompatibility for major version number changes is void. (The most important datatype that this change affects is MPI_DOUBLE_PRECISION: users will need to recompile their code with v1.3...) Please raise Your hand if anybody cares. Sun cares very much about this for the exact reason you state (Binary compatibility). I'd prefer this ddt is placed at the end of the list. I think we should try to avoid binary compatibility changes at the MPI layer if we can, even between our "major" releases. Especially if they don't take lots of work. Now if only we would stop changing the size of ompi_communicator_t :). Brian
Re: [OMPI devel] openib coord teleconf
It's today. If there's time left on the main OMPI call, we'll do it there. Otherwise, I'll tell everyone on today's call what the number is for after the OMPI call. On Jun 19, 2007, at 10:38 AM, Andrew Friedley wrote: oops, was this yesterday? If it was today, whats the number? Andrew Jeff Squyres wrote: On Jun 13, 2007, at 3:38 PM, Andrew Friedley wrote: I'd like to call in as some of this applies to UD as well, is that okay? Sounds good. Andrew Jeff Squyres wrote: On Jun 13, 2007, at 2:41 PM, Gleb Natapov wrote: Pasha tells me that the best times for Ishai and him are: - 2000-2030 Israel time - 1300-1300 US Eastern - 1100-1130 US Mountain - 2230-2300 India (Bangalore) Although they could also do the preceding half hour as well. Depends on the date. The closest I can at 20:00 is June 19. Oops! I left out the date -- sorry. I meant to say Monday, June 18th. And I got the US eastern time wrong; that should have been noon, not 1300. 20:00 Israel June 19th is right after the weekly OMPI teleconf; want to do it then? ___ devel mailing list de...@open-mpi.org http://www.open-mpi.org/mailman/listinfo.cgi/devel ___ devel mailing list de...@open-mpi.org http://www.open-mpi.org/mailman/listinfo.cgi/devel -- Jeff Squyres Cisco Systems
Re: [OMPI devel] MPI_REAL2 support and Fortran ddt numbering
Hello, On Tuesday 19 June 2007 16:41, Brian Barrett wrote: > >> Please raise Your hand if anybody cares. > > > > Sun cares very much about this for the exact reason you state (Binary > > compatibility). > > I'd prefer this ddt is placed at the end of the list. > > I think we should try to avoid binary compatibility changes at the > MPI layer if we can, even between our "major" releases. Especially > if they don't take lots of work. Now if only we would stop changing > the size of ompi_communicator_t :). Alright. As suggested, the two missing parts are committed. To the unsuspecting Fortran app, everything should look the same... With best regards, Rainer -- Dipl.-Inf. Rainer Keller http://www.hlrs.de/people/keller High Performance Computing Tel: ++49 (0)711-685 6 5858 Center Stuttgart (HLRS) Fax: ++49 (0)711-685 6 5832 POSTAL:Nobelstrasse 19 email: kel...@hlrs.de ACTUAL:Allmandring 30, R.O.030AIM:rusraink 70550 Stuttgart
[OMPI devel] Unreliable Datagram BTL
Galen asked for a writeup of where the UD BTL support is at and what (important) issues remain, so here it is. Right now, to ensure MPI guaranteed delivery semantics the DR PML must be used with UD -- the UD BTL does not implement its own reliability. The best solution would be to implement a lightweight reliability protocol within the UD BTL, and would be most effective with a progress thread. Progress threads are a whole other issue.. with a quick implementation, I was hitting all sorts of segfaults in the PML. The UD BTL seems unique in that it is common for messages to be received and passed up to the PML out of order. I can revisit this and file some bug reports if desired sooner than later. I know of one outstanding bug -- any of the tests in the intel suite using buffered sends fail with incorrect data. I've shown this problem to George, Galen, and Brian and have yet to come up with a fix -- it appears to be an issue with messages arriving at the PML out of order, at which point the PML has no datatype information so cannot reassemble the messages correctly. This would need to be fixed for 1.3. When the UD BTL goes into the trunk, it will always de-select itself unless specifically requested with the MCA btl parameter (i.e. -mca btl ud,self). This prevents the UD BTL from being used by default along with the existing RC (openib) BTL and possibly lowering performance. Some minor issues.. when it hits the trunk, it will be called 'ofud', short for OpenFabrics Unreliable Datagrams. Currently RDMA CM is not used, though it will not be hard to switch over (doing it at the same time as the openib BTL seems appropriate to me). Andrew
