Conference Paper

Dynamic multi phase scheduling for heterogeneous clusters.

Dept. of Electr. & Comput. Eng., Athens Nat. Tech. Univ., Greece;
DOI: 10.1109/IPDPS.2006.1639308 Conference: 20th International Parallel and Distributed Processing Symposium (IPDPS 2006), Proceedings, 25-29 April 2006, Rhodes Island, Greece
Source: DBLP

ABSTRACT Distributed computing systems are a viable and less
expensive alternative to parallel computers. However,
concurrent programming methods in distributed systems have not been studied as extensively as for parallel computers. Some of the main research issues are
how to deal with scheduling and load balancing of such a
system, which may consist of heterogeneous computers.
In the past, a variety of dynamic scheduling schemes
suitable for parallel loops (with independent iterations)
on heterogeneous computer clusters have been obtained
and studied. However, no study of dynamic schemes
for loops with iteration dependencies has been reported
so far. In this work we study the problem of scheduling loops with iteration dependencies for heterogeneous
(dedicated and non-dedicated) clusters. The presence
of iteration dependencies incurs an extra degree of dif-
ficulty and makes the development of such schemes
quite a challenge. We extend three well known dynamic schemes (CSS, TSS and DTSS) by introducing
synchronization points at certain intervals so that processors compute in pipelined fashion. Our scheme is
called dynamic multi-phase scheduling (DMPS) and
we apply it to loops with iteration dependencies. We
implemented our new scheme on a network of heterogeneous computers and studied its performance. Through
extensive testing on two real-life applications (the heat
equation and the Floyd-Steinberg algorithm), we show
that the proposed method is efficient for parallelizing
nested loops with dependencies on heterogeneous systems.

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