Parallel Programming: for Multicore and Cluster Systems- P44 pdf

... coefficient matrix A = (a ij ) ∈ R n×n is symmetric and positive definite, i.e., if a ij = a ji and x T Ax > 0 for all x ∈ R n with x = 0. For a symmetric and positive definite n × n matrix A ∈ R n×n there ... Factorization for Sparse Matrices 431 identify its original position in the full matrix. Thus, a compressed storage scheme for sparse matrices needs the space for the n...

Ngày tải lên: 03/07/2014, 16:21

... F 00  ·  x (k) R x (k) B  +ω  b 1 b 2  . For a parallel implementation the component form of this system is used. On the other hand, for the convergence results the matrix form and the iteration matrix have ... another source of parallelism, which is a coarse-grained parallelism of two linear algebra operations performed in parallel, in contrast to the fine-grained parallelism ex...

Ngày tải lên: 03/07/2014, 22:20

... description of XY routing for two-dimensional meshes and E-cube routing for hypercubes as typical examples for dimension-order routing algorithms. XY Routing for Two-Dimensional Meshes For a two-dimensional ... {n 1 , ,n k } exists such that for 1 ≤ i < k each message N i uses a link n i for transmission and waits for the release of link n i+1 which is currently used f...

Ngày tải lên: 03/07/2014, 16:20

... matrices [127]. The GA approach is provided as a library with interfaces for C, C++, and Fortran for different parallel platforms. The GA approach is based on a global address space in which global ... synchronization are performed by the runtime system, and no low-level lock synchronization must be performed. Chapel has been developed by Cray Inc. as a new parallel language for...

Ngày tải lên: 03/07/2014, 16:21

... team. This fork operation is performed implicitly. The program code inside the parallel construct is called a parallel region and is executed in parallel by all threads of the team. The parallel ... sophisticated implementa- tions may queue command for execution by one of a set of threads. For multicore processors, several threads are typically available for the execution of...

Ngày tải lên: 03/07/2014, 16:21

... memory accesses must be atomic and since memory accesses must be performed one after another. There- fore, processors may have to wait for quite a long time before memory accesses that they have ... read and write operations which lie in the program before the synchronization operation are completed before the synchronization operation. • The synchronization operation is completed befor...

Ngày tải lên: 03/07/2014, 22:20

... t1 and t2 are temporary array variables.  More information on parallel loops and their execution as well as on transforma- tions to improve parallel execution can be found in [142, 175]. Parallel ... used for distributed address space. The fork–join concept is, for example, used in OpenMP for the creation of threads executing a parallel loop, see Sect. 6.3 for more detail...

Ngày tải lên: 03/07/2014, 22:20

... communication partners in the form source/dest are given in this order. For example, for the process with rank=5,itiscoords[1]=1, and there- fore source=9 (lower neighbor in dimension 0) and dest=1 (upper ... and source for each pro- cess. These are then used as parameters for MPI Sendrecv(). The following diagram illustrates the exchange. For each process, its rank, its Carte...

Ngày tải lên: 03/07/2014, 22:20

... structure and initializing it with the argument values provided. Moreover, the threads used for the execution of the tasks are generated and their IDs are stored in tpl->threads[i] for i=0, ... no threads waiting for cond. If there are several threads waiting for cond, one of them is selected to be woken up. For the selection, the priorities of the wait- ing threads and the...

Ngày tải lên: 03/07/2014, 22:20

... entries and additional information about the row and column indices to 426 7 Algorithms for Systems of Linear Equations * * * j * * * * * * j j * * * j * * * * * * j data items used for the computation ... an equality for column ˜ a j = (a 1 j , ,a nj ) and columns ˜ l k = (l 1k , ,l nk )fork ≤ j: ˜ a j = j  k=1 l jk ˜ l k leading to l jj ˜ l j = ˜ a j − j−1  k=1 l jk ˜ l k (7.6...

Ngày tải lên: 03/07/2014, 22:20