Re: [OMPI users] Cell EIB support for OpenMPI

2007-03-23 Thread Marcus G. Daniels
George Bosilca wrote: All in all we end up with a multi-hundreds KB library which in most of the applications will be only used at 10%. Seems like it ought to be possible to do some coverage analysis for a particular application and figure out what parts of the library (and user code) to ma

Re: [OMPI users] Cell EIB support for OpenMPI

2007-03-23 Thread George Bosilca
The main problem with MPI is the huge number of function in the API. Even if we implement only the 1.0 standard we still have several hundreds of functions around. Moreover, an MPI library is far from being a simple self-sufficient library, it requires a way to start and monitor processes,

Re: [OMPI users] Cell EIB support for OpenMPI

2007-03-23 Thread Mike Houston
Marcus G. Daniels wrote: Marcus G. Daniels wrote: Mike Houston wrote: The main issue with this, and addressed at the end of the report, is that the code size is going to be a problem as data and code must live in the same 256KB in each SPE. They mention dynamic overlay loading,

Re: [OMPI users] Cell EIB support for OpenMPI

2007-03-23 Thread Marcus G. Daniels
Marcus G. Daniels wrote: Mike Houston wrote: The main issue with this, and addressed at the end of the report, is that the code size is going to be a problem as data and code must live in the same 256KB in each SPE. They mention dynamic overlay loading, which is also how we deal with large

Re: [OMPI users] Cell EIB support for OpenMPI

2007-03-22 Thread Marcus G. Daniels
Mike Houston wrote: The main issue with this, and addressed at the end of the report, is that the code size is going to be a problem as data and code must live in the same 256KB in each SPE. Just for reference, here are the stripped shared library sizes for OpenMPI 1.2 as built on a Mercury Ce

Re: [OMPI users] Cell EIB support for OpenMPI

2007-03-22 Thread Mike Houston
That's pretty cool. The main issue with this, and addressed at the end of the report, is that the code size is going to be a problem as data and code must live in the same 256KB in each SPE. They mention dynamic overlay loading, which is also how we deal with large code size, but things get t

[OMPI users] Cell EIB support for OpenMPI

2007-03-22 Thread Marcus G. Daniels
Hi, Has anyone investigated adding intra chip Cell EIB messaging to OpenMPI? It seems like it ought to work. This paper seems pretty convincing: http://www.cs.fsu.edu/research/reports/TR-061215.pdf