Parallel Programming: for Multicore and Cluster Systems- P13 pot

Ngày tải lên: 03/07/2014, 22:20

... Pthreads and Sect. 6.2.3 for Java threads. 114 3 Parallel Programming Models j, j + p, , j + p · ( n/p−1 ) for j ≤ n mod p and j, j + p, , j + p · ( n/p−2 ) for n mod p < j ≤ p. For the ... partitioning. In a parallel program, the processors perform computations only on their part of the data. Data distributions can be used for parallel programs for distributed as...

Ngày tải lên: 03/07/2014, 16:20

... techniques for selecting paths through networks and switching techniques for message forwarding over a given path. Section 2.7 considers memory hierarchies of sequential and parallel plat- forms and ... the resources of parallel platforms and to exchange data and information between these resources. Interconnection networks also play an impor- tant role in multicore proces...

Ngày tải lên: 03/07/2014, 16:20

... using edges between nodes for communication, can be re-formulated for G with the mapping function σ , thus using corresponding edges in G for communication. The network of a parallel system should ... implies that there is an edge between node α 0 α j α k−1 and node α 0 ¯α j α k−1 for 0 ≤ j ≤ k − 1 where ¯α j = 1for j = 0 and ¯α j = 0for j = 1. Thus, there is an edge betwe...

Ngày tải lên: 03/07/2014, 16:20

... receive buffer and to select the output channel to be used by inspecting the header informa- tion of the packet. Thus, for a path of length l, the entire time for packet transmission with store -and- forward ... path have different bandwidths as this is typically the case in wide area networks (WANs). In this case, store -and- forward routing allows the utilization of the full bandwidth...

Ngày tải lên: 03/07/2014, 16:20

... Number of Threads and Sequentialization Depending on the design and implementation, the runtime of a parallel program based on threads can be quite different. For the design of a parallel program ... the case for the Pthreads library, see Sect. 6.1.10 for more details. The scheduler of the operating system on the other hand is tuned for an efficient use of the hardware resource...

Ngày tải lên: 03/07/2014, 16:21

... real parallel machines for a large class of application areas in a satisfactory way. One of the reasons is that there is a large variety of different architectures for parallel machines and the ... addition operations and r multiplication operations are performed. The time for a single-accumulation operation depends on the specific intercon- nection network and we consider the...

Ngày tải lên: 03/07/2014, 16:21

... queue and executes the operation (REQ READ, REQ WRITE, or REQ QUIT) specified in the request. For the REQ READ operation, the prompt specified with the request is output and a line is read in and ... object has to be allocated and initial- ized before using the attribute object as parameter of pthread create().An attribute object for threads has type pthread attr t. Before an attrib...

Ngày tải lên: 03/07/2014, 16:21

... reduction oper- ation performed in parallel by the threads of a team. For this kind of calculation OpenMP provides the reduction clause, which can be used for parallel, sections, and for constructs. The ... The second parallel loop performs the matrix multiplication in a nested for loop. The for construct applies to the first for loop with iteration variable row and, thus,...

Ngày tải lên: 03/07/2014, 16:21

... operations are performed for one entry according to Formula (7.4), the computation time is max q∈P N col>k q · N row>k q ·2t op . In total, the parallel execution for all phases and all steps is T ... 3t op , and n(n−1)(2n−1) 3p · t op are independent of the specific choice of p 1 and p 2 and need not be considered. The terms n(n−1) 2 1 p 1 t op and t c p 2 (n − 1) log p...

Ngày tải lên: 03/07/2014, 16:21