Section: New Results

Middleware and Experimental Testbeds

Participants : Olivier Richard, Yves Denneulin, Jean-François Méhaut.

TakTuk: Middelware for adaptive deployment of remote execution

In [21] , we describe TakTuk, which a middleware that deploys efficiently parallel remote executions on large scale grids (thousands of nodes). This tool is mostly intended for interactive use, in particular distributed machines administration and parallel applications development. Thus, it has to minimize the time required to complete the whole deployment process.

To achieve this minimization, we propose and validate a remote execution deployment model inspired by the real world behavior of standard remote execution protocols (rsh and ssh). From this model and from existing works in networking, we deduce an optimal deployment algorithm for the homogeneous case. Unfortunately, this optimal algorithm does not translate directly to the heterogeneous case.

Therefore, we derive from the theoretical solution a heuristic based on dynamic work-stealing that adapts to heterogeneities (processors, links, load, ...). The underlying principle of this heuristic is the same as the principle of the optimal algorithm: to deploy nodes as soon as possible. Experiments assess TakTuk's efficiency and show that TakTuk scales well to thousands of nodes. Compared to similar tools, TakTuk ranks among the best while offering more features and versatility. In particular, TakTuk is the only tool well-suited for remote execution deployment on grids or more heterogeneous platforms.