P2P File Sharing for P2P Computing

in Multiagent and Grid Systems (2009), 2009/5(2), 137-164

The transfer of large input data files in P2P computing Grids often leads to delays in Task completion times. Existing research related to this topic has been focused on the spatial grouping of Tasks, i.e ... [more ▼]

The transfer of large input data files in P2P computing Grids often leads to delays in Task completion times. Existing research related to this topic has been focused on the spatial grouping of Tasks, i.e. reuse of available data through data caching and data-aware scheduling. However, it tends to decrease the level of parallelism of Task execution. In this paper, this issue is addressed by integrating the BitTorrent P2P file sharing protocol, a novel Task selection scheduling algorithm, an existing online, data-aware Resource selection algorithm (similar to Storage Affinity), and caching support. These algorithms have been implemented in the Lightweight Bartering Grid middleware. The Java implementation relies exclusively on Free and Open Source data transfer software (Azureus, Apache FTP server, edtFTPj). The proposed data transfer architecture does not need Predictive Communications Ordering or an explicit deployment of an overlay network. It is also easily deployable. Our main contribution is the joint use of P2P computing and P2P file sharing technologies, enabling a highly scalable and adaptive data transfer architecture to support P2P computing. [less ▲]

Scheduling Data-Intensive Bags of Tasks in P2P Grids with BitTorrent-enabled Data Distribution

in Fortino, Giancarlo; Mastroianni, Carlo; Pierre, Guillaume (Eds.) Proceedings of the Second Workshop on Use of P2P, GRID and Agents for the Development of Content Networks (2007, June 26)

Scheduling Data-Intensive Bags of Tasks in P2P Grids leads to transfers of large input data files, which cause delays in completion times. We propose to combine several existing technologies and patterns ... [more ▼]

Scheduling Data-Intensive Bags of Tasks in P2P Grids leads to transfers of large input data files, which cause delays in completion times. We propose to combine several existing technologies and patterns to perform efficient data-aware scheduling: (1) use of the BitTorrent P2P file sharing protocol to transfer data, (2) data caching on computational Resources, (3) use of a data-aware Resource selection scheduling algorithm similar to Storage Affinity, (4) a new Task selection scheduling algorithm (Temporal Tasks Grouping), based on the temporally grouped scheduling of Tasks sharing input data files. Data replication is also discussed. The proposed approach does not need an overlay network or Predictive Communications Ordering, making our operational implementation of a P2P Grid middleware easily deployable in unstructured P2P networks. Experiments show that performance gains are achieved by combining BitTorrent, caching, Storage Affinity and Temporal Tasks Grouping. This work can be summarized as combining P2P Grid computing and P2P data transfer technologies. [less ▲]

Approximate Policy Iteration for Closed-Loop Learning of Visual Tasks

(2006, September)

Approximate Policy Iteration (API) is a reinforcement learning paradigm that is able to solve high- dimensional, continuous control problems. We propose to exploit API for the closed-loop learning of ... [more ▼]

Approximate Policy Iteration (API) is a reinforcement learning paradigm that is able to solve high- dimensional, continuous control problems. We propose to exploit API for the closed-loop learning of mappings from images to actions. This approach requires a family of function approximators that maps visual percepts to a real-valued function. For this purpose, we use Regression Extra-Trees, a fast, yet accurate and versatile machine learning algorithm. The inputs of the Extra-Trees consist of a set of visual features that digest the informative patterns in the visual signal. We also show how to parallelize the Extra-Tree learning process to further reduce the computational expense, which is often essential in visual tasks. Experimental results on real-world images are given that indicate that the combination of API with Extra-Trees is a promising framework for the interactive learning of visual tasks. [less ▲]

Task-Driven Discretization of the Joint Space of Visual Percepts and Continuous Actions

in European Conference on Machine Learning (2006)

An effective decision procedure for linear arithmetic over the integers and reals

in ACM transactions on Computational Logic (2005), 6(3), 614--633

This article considers finite-automata-based algorithms for handling linear arithmetic with both real and integer variables. Previous work has shown that this theory can be dealt with by using finite ... [more ▼]

This article considers finite-automata-based algorithms for handling linear arithmetic with both real and integer variables. Previous work has shown that this theory can be dealt with by using finite automata on infinite words, but this involves some difficult and delicate to implement algorithms. The contribution of this article is to show, using topological arguments, that only a restricted class of automata on infinite words are necessary for handling real and integer linear arithmetic. This allows the use of substantially simpler algorithms, which have been successfully implemented. [less ▲]

Interactive Learning of Mappings from Visual Percepts to Actions

in 22nd International Conference on Machine Learning (2005)

Apprentissage Interactif de Liaisons Directes entre Perceptions Visuelles et Actions

in Actes du Congrès ORASIS (2005)

Interactive Selection of Visual Features through Reinforcement Learning

in 24th SGAI International Conference on Innovative Techniques and Applications of Artificial Intelligence (2004)

On the Use of Weak Automata for Deciding Linear Arithmetic with Integer and Real Variables

in Lecture Notes in Computer Science (2001), 2083

This paper considers finite-automata based algorithms for handling linear arithmetic with both real and integer variables. Previous work has shown that this theory can be dealt with by using finite ... [more ▼]

This paper considers finite-automata based algorithms for handling linear arithmetic with both real and integer variables. Previous work has shown that this theory can be dealt with by using finite automata on in finite words, but this involves some difficult and delicate to implement algorithms. The contribution of this paper is to show, using topological arguments, that only a restricted class of automata on in finite words are necessary for handling real and integer linear arithmetic. This allows the use of substantially simpler algorithms and opens the path to the implementation of a usable system for handling this combined theory. [less ▲]