Random walks, heat equation and distributed algorithms

New results are obtained concerning the analysis of the storage allocation algorithm which permits one to maintain two stacks inside a shared (continuous) memory area of fixed size m and of the banker's algorithm (a deadlock avoidance policy). The formulation of these problems is in terms of random walks inside polygonal domains in a two-dimensional lattice space with several reflecting barriers and one absorbing barrier. For the two-stacks problem, the return time to the origin, the time to absorption, the last leaving time from the origin and the number of returns to the origin before absorption are investigated. For the banker's algorithm, the trend-free absorbed random walk is analysed with numerical methods. We finally analyse the average excursion along one axis for the classical random walk: an analytic method enables us to deduce asymptotic results for this average excursion. © 1994.SCOPUS: ar.j