Logo des Repositoriums

Auflistung nach Autor:in "Rehm, Wolfgang"

1 - 3 von 3
  • Konferenzbeitrag
    Adding low-cost hardware barrier support to small commodity clusters
    (ARCS'06, 19th International Conference on Architecture of Computing Systems, 2006) Hoefler, Torsten; Mehlan, Torsten; Mietke, Frank; Rehm, Wolfgang
  • Konferenzbeitrag
    An optimized ZGEMM implementation for the Cell BE
    (9th workshop on parallel systems and algorithms – workshop of the GI/ITG special interest groups PARS and PARVA, 2008) Schneider, Timo; Hoefler, Torsten; Wunderlich, Simon; Mehlan, Torsten; Rehm, Wolfgang
    The architecture of the IBM Cell BE processor represents a new approach for designing CPUs. The fast execution of legacy software has to stand back in order to achieve very high performance for new scientific software. The Cell BE consists of 9 independent cores and represents a new promising architecture for HPC systems. The programmer has to write parallel software that is distributed to the cores and executes subtasks of the program in parallel. The simplified Vector-CPU design achieves higher clock-rates and power efficiency and exhibits predictable behavior. But to exploit the capabilities of this upcoming CPU architecture it is necessary to provide optimized libraries for frequently used algorithms. The Basic Linear Algebra Subprograms (BLAS) provide functions that are crucial for many scientific applications. The routine ZGEMM, which computes a complex matrix–matrix–product, is one of these functions. This article describes strategies to implement the ZGEMM routine on the Cell BE processor. The main goal is achieve highest performance. We compare this optimized ZGEMM implementation with several math libraries on Cell and other modern architectures. Thus we are able to show that our ZGEMM algorithm performs best in comparison to the fastest publicly available ZGEMM and DGEMM implementations for Cell BE and reasonably well in the league of other BLAS implementations.
  • Konferenzbeitrag
    VIA2SISCI – A new library that provides the VIA semantics forsci connected clusters
    (ARCS 2004 – Organic and pervasive computing, 2004) Mehlan, Torsten; Rehm, Wolfgang
    Normally the SISCI interface provides a Distributed Shared Memory (DSM) [PTM97] abstraction using the Scalable Coherent Interface (SCI). This paper describes and discusses the design and the concepts behind a library called VIA2SISCI that we have developed. The library maps the semantics of the Virtual Interface Architecture (VIA) to SISCI-semantics and establishes a middleware between SISCI and highlevel communication facilities. We focus on several important concepts of VIA that had to be mapped to the SISCI services. The presented concepts may be interesting and useful beyond the scope of this paper.