Efficient Schemes for Limited Directory-Based DSMs Using Multidestination Message Passing

Abstract

: Many limited directory schemes have been proposed in the literature to build costeffective DSM systems. However, all these schemes are based on networks supporting only point-to-point (unicast) message passing. New generation networks are providing architectural support to implement collective communication operations (broadcast, multicast, reduction, etc.) with reduced latency. This paper explores the impact of such architectural support in designing efficient and more cost-effective limited directory schemes. The study is carried out for wormhole k-ary n-cube networks supporting multidestination message passing mechanism. The study in this paper is carried out along two major directions. First, a variation of the dir i B scheme to work with multidestination-based broadcast and gather operations is proposed. This scheme is defined as m dir i B scheme. Next, two coarse vector schemes (m dir i CB 1 and m dir i CB 2 ) are proposed to work efficiently with selective broadcast operation..