HPCN at ENEA

PQE-1 - Run Time Environment (RTE)

In a general-purpose system, it is essential, on one side, to hide the details of the physical machine to the languages and the programming tools, and, on the other side, to make visible only the fundamental elements for the structuring of programs, and to provide a set of parameters linked to the "execution cost" of programs on the specific physical machine.

The above tasks are entrusted to an "intermediate virtual machine" also called Run Time Environment (RTE). The RTE supports the realization of upper level software environments and guarantees their portability on different hardware platforms. It also performs the basic cooperation mechanisms for a general and efficient support to parallel programs built according to different computational models and/or granularity levels. In particular, the RTE implements:

inter-process communication (essentially according to the MPI standard),
virtual shared memory,
uniform vision of the input/output devices.

In PQE1, the RTE is made of:

the Message Passing Interface (MPI) standard for the CS2;
Distributed Virtual Shared Memory (DVSM) mechanisms.
low level interfacing between the MIMD-CS2 and SIMD-Quadrics/APE100 subsystems made possible by a subset of RTE’s software mechanisms as well as by the HiPPI physical channels.


For more details, see the Documentation and the References.

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