Parallel Computing Lecture 6 - Sorting Algorithms

Parallel Computing - Lecture 6 - Sorting Algorithms (2)

• The lecture covers compare-and-exchange operations, sorting algorithms, and data partitioning methods used in parallel computing.
• Compare and exchange operations place two variables in the correct order. If variable A is greater than variable B, their values are swapped. This is a fundamental operation in many sorting algorithms.
• Internal sort algorithms typically involve a series of compare-and-exchange operations.
• Parallel compare-and-exchange operations can be introduced to improve performance. Methods are provided to prevent deadlock in parallel implementations.
• Data partitioning divides a list of numbers among a set of processors, such that each processor operates on a subset of the data, making parallel sort operations possible.
• Data is distributed among processors (P1, P2).
• Data partitioning and merging between processors are illustrated in figures 9.6 and 9.7.
• Sorting algorithms like Odd-Even and Shell sort are discussed, explaining their steps and providing details of how to implement them in a parallel setting.
• Shell Sort partitions data based on groups/shells of processors. Compare and exchange operations occur between corresponding members of these shells, gradually sorting the data.
• Algorithms like Odd-Even, Shell sort and Bitonic Sort are described in further detail including their procedures including possible implementation solutions and complexities.
• The complexity of compare-and-exchange is assessed regarding computation and communication. This consideration is critical for evaluating the efficiency of parallel implementations.
• A sequential bubble sort algorithm is detailed, providing a reference point for contrast with parallel versions.
• The time complexity of the sequential bubble sort algorithm is O(n^2).
• Parallel bubble sort, odd-even sort and shell sort algorithms are compared with their time complexities examined.
• Bitonic sort is detailed with its process of sorting, implementation methods and recursive operations.
• Bitonic sort is also characterized by its recursive approach for sorting sequences of numbers.
• The bitonic sort method is based on the concept of bitonic sequences.
• Sorting networks are circuits performing sorting tasks.
• Details regarding the construction, implementation and utilization of sorting networks are outlined in the text.
• Parallel implementation approaches for the bitonic sort operation are demonstrated, detailing the use of MPI libraries for communication between processors.

This lecture focuses on sorting algorithms in parallel computing, highlighting compare-and-exchange operations and data partitioning methods. Learn how these operations enhance sorting efficiency and how to avoid deadlocks in parallel implementations. Various internal sort algorithms and their applications are also discussed.