Parallel programming for multicore and cluster systems p9

... for the L1 cache, between 15 and 25 cycles for the L2 cache, between 100 and 1000 cycles for the main memory, and between 10 and 100 million cycles for the hard disc [137] 2.7.3 Cache Coherency ... to and the USE bit of the other block in the set is set to This is performed for each memory access Thus, 2.7 Caches and Memory Hierarchy 73 the block whose USE bit is has bee...

Ngày tải lên: 03/07/2014, 16:20

... for the L1 cache, between 15 and 25 cycles for the L2 cache, between 100 and 1000 cycles for the main memory, and between 10 and 100 million cycles for the hard disc [137] 2.7.3 Cache Coherency ... to and the USE bit of the other block in the set is set to This is performed for each memory access Thus, 2.7 Caches and Memory Hierarchy 73 the block whose USE bit is has bee...

Ngày tải lên: 03/12/2015, 23:42

... important parallel programming techniques that are necessary for developing efficient programs for multicore processors as well as for parallel cluster systems or supercomputers Both shared and distributed ... presents parallel programming models, performance models, and parallel programming environments for message passing and shared memory models, including MPI, Pth...

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 platforms and discusses ... the resources of parallel platforms and to exchange data and information between these resources Interconnection networks also play an important role in multicore pr...

Ngày tải lên: 03/07/2014, 16:20

... are usually based on standard computers and even standard network topologies The entire cluster is addressed and programmed as a single unit The popularity of clusters as parallel machines comes ... sequential processes and which will be considered in more detail in 14 Parallel Computer Architecture Chaps and To perform message-passing, two processes PA and PB on different nod...

Ngày tải lên: 03/07/2014, 16:20

... separate thread available for execution Therefore, the application program must apply parallel programming techniques to get performance improvements for SMT processors 2.4.2 Multicore Processors ... techniques of parallel programming have to be used for the implementation 24 Parallel Computer Architecture 2.4.3 Architecture of Multicore Processors There are many different de...

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 ... xμ | = and x j = x j for all j = μ In the case that the mesh has the same extension in all dimensions (also called √ symmetric mesh), i.e., n j = r = d n for all j = 1, , d, and t...

Ngày tải lên: 03/07/2014, 16:20

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

Ngày tải lên: 03/07/2014, 16:20

... the left) of β and selects the output link for forwarding the message according to the following rule: • for βk = 0, the message is forwarded over the upper link of the switch and • for βk = 1, ... 2.6 Routing and Switching Fig 2.22 Illustration of turns for a two-dimensional mesh with all possible turns (top), allowed turns for X Y routing (middle), and allowed turns for...

Ngày tải lên: 03/07/2014, 16:20

... including local and wide area networks, and popular protocols like TCP contain sophisticated mechanisms for flow control to obtain a high effective network bandwidth, see [110, 139] for more details ... Caches and Memory Hierarchy 65 which are currently used most Today, two or three levels of cache are used for each processor, using a small and fast L1 cache and larger, but slo...

Ngày tải lên: 03/07/2014, 16:20

... all memory accesses must be atomic and since memory accesses must be performed one after another Therefore, processors may have to wait for quite a long time before memory accesses that they have ... in (4) Thus, both P1 and P2 may print the old value for x1 and x2 , respectively Partial store ordering (PSO) models relax both the W → W and the W → R ordering required for sequent...

Ngày tải lên: 03/07/2014, 16:20

... of single systems and provide an abstract view for the design and analysis of parallel programs 3.1 Models for Parallel Systems In the following, the types of models used for parallel processing ... assignments of Fortran 90/95, see [49, 175, 122] Other examples for data -parallel programming languages are C* and data -parallel C [82], PC++ [22], DINO [151], and High-P...

Ngày tải lên: 03/07/2014, 16:20

... where t1 and t2 are temporary array variables More information on parallel loops and their execution as well as on transformations to improve parallel execution can be found in [142, 175] Parallel ... be 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 detai...

Ngày tải lên: 03/07/2014, 16:20

... memory organization of the parallel platform used In the following, we give a first overview on techniques for information exchange for shared address space in Sect 3.5.1 and for distributed address ... array elements 114 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 example n = 14...

Ngày tải lên: 03/07/2014, 16:20

... are no dependencies and the loops over i and j can be exchanged For a parallel implementation, the row- and column-oriented representations of matrix A give rise to different parallel implementation ... arrays A, b, and c for a shared memory system 3.6 Parallel Matrix–Vector Product 129 3.6.2 Parallel Computation of the Linear Combinations For a distributed memory machin...

Ngày tải lên: 03/07/2014, 16:20