Changes between Version 15 and Version 16 of developer_information

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Timestamp:
07/12/11 12:56:06 (13 years ago)
Author:
piontek
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  • developer_information

    v15 v16  
    1010The Message Passing Interface (MPI) is de facto a standard in the domain of parallel applications demanding computational resources that are beyond what single machine can provide. It delivers end-users both the programming interface consisting of simple communication primitives and the environment for spawning and monitoring MPI processes.  
    1111A variety of implementations of the MPI standard is available (both as commercial and open source). In !QosCosGrid, it was decided to use OpenMPI implementation of the MPI 2.0 standard as input for further enhancements. Of key importance were the inter-cluster communication techniques that deal with firewalls and Network Address Translation. In addition, the mechanism for spawning new processes in OpenMPI needed to be integrated with !QosCosGrid-developed middleware. The extended version of the OpenMPI framework was named [http://www.qoscosgrid.org/trac/qcg-openmpi QCG-OMPI]  (where QCG stands for !QosCosGrid). The extensions were three-fold:  
    12 1. - internally, QCG-OMPI improves the MPI library by featuring multiple connectivity techniques to enable, when possible, direct connections between MPI ranks that are located in remote clusters potentially separated by firewalls;  
    13 1. - the MPI standard was extended to comply with the !QosCosGrid semi-opportunistic approach, by providing a new interface to describe the actual topology provided by the meta-scheduler;  
    14 1. - many MPI collective operations were upgraded to be hierarchy-aware, and optimized for the Grid.  
     121. internally, QCG-OMPI improves the MPI library by featuring multiple connectivity techniques to enable, when possible, direct connections between MPI ranks that are located in remote clusters potentially separated by firewalls;  
     131. the MPI standard was extended to comply with the !QosCosGrid semi-opportunistic approach, by providing a new interface to describe the actual topology provided by the meta-scheduler;  
     141. many MPI collective operations were upgraded to be hierarchy-aware, and optimized for the Grid.  
    1515 
    1616== QCG !ProActive ==