Edge reductions model the ability of speeding up communication between processors in a network. In this paper we consider performing edge reductions in a tree network so that the diameter of the tree is minimized. The diameter is directly related to the time needed to broadcast a message. In particular, fOr non-blocking message communication ignoring start-up costs, the diameter corresponds to ...

The behavior and performance of MPI non-blocking message passing operations are sensitive to implementation specifics as they are heavily dependant on available system level buffers. In this paper we investigate the behavior of non-blocking communication primitives provided by popular MPI implementations and propose strategies for these primitives than can reduce processor synchronization overh...

In this paper, the concept of “computing checkpoint” is introduced, and then an efficient coordinated checkpoint algorithm is proposed. The algorithm combines the two approaches of reducing the overhead associated with coordinated checkpointing, which one is to minimize the processes which take checkpoints and the other is to make the checkpointing process non-blocking. Through piggybacking the...

The performance of a parallel matrix-matrix-multiplication routine with the same functionality as DGEMM of BLAS3 was tested for different numbers of nodes on a 32-node iPSC/860. The routine was then tuned for maximum performance on this particular computer system. Small changes in the original code lead to substantially higher performance and in all tested configurations there is a critical mat...

In the context of e-commerce, execution atomicity is an important property for mobile agents. A mobile agent executes atomically, if either all its operations succeed, or none at all. This requires to solve an instance of the atomic commitment problem. However, it is important that failures (e.g., of machines or agents) do not lead to blocking of transactional mobile agents, i.e., agents that e...

Asymptotically nonblocking networks are O(log2 N) depth self-routing permutation devices in which blocking probability vanishes when N (the number of network inputs) increases. This behavior does not guarantee, also for very large N , that all information always and simultaneously reaches its destination (and consequently that a whole permutation passes through the device) which is a requiremen...

Web integration systems are able to provide transparent and uniform access to heterogeneous Web data sources by integrating views of Linked Data, Web Service results, or data extracted from the Deep Web. However, given the potential large number of views, query engines of Web integration systems have to implement execution techniques able to scale up to real-world scenarios and efficiently exec...

We present new non-blocking array-based shared stack and queue implementations. We sketch proofs of correctness and amortized time analyses for the algorithms. To the best of our knowledge, our stack algorithm is the first practical array-based one and it is the first time that bounded counter values are employed to implement a shared stack and queue. We verify the correctness of our algorithms...

Non-contiguous subsequence pattern queries search for symbol instances in a long sequence that satisfy some soft temporal constraints. In this paper, we propose a methodology that indexes long sequences, in order to efficiently process such queries. The sequence data are decomposed into tables and queries are evaluated as multiway joins between them. We describe non-blocking join operators and ...

This paper shows how downward simulation can be checked using existing temporal logic model checkers. In particular, we show how the branching time temporal logic CTL can be used to encode the standard downward simulation conditions. We do this for both a blocking, or guarded, interpretation of operations (often used when specifying reactive systems) as well as the more common non-blocking inte...