Multithreaded transactions in scientific computing. The Growth06_v2 program

Abstract

Writing a concurrent program can be more difficult than writing a sequential program. Programmer needs to think about synchronization, race conditions and shared variables. Transactions help reduce the inconvenience of using threads. A transaction is an abstraction, which allows programmers to group a sequence of actions on the program into a logical, higher-level computation unit. This paper presents a new version of the GROWTHGr and GROWTH06 programs. New version program summary Program title: GROWTH06_v2 Catalogue identifier: ADVL_v2_1 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/ADVL_v2_1.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.html No. of lines in distributed program, including test data, etc.: 65 255 No. of bytes in distributed program, including test data, etc.: 865 985 Distribution format: tar.gz Programming language: Object Pascal Computer: Pentium-based PC Operating system: Windows 9x, XP, NT, Vista RAM: more than 1 MB Classification: 4.3, 7.2, 6.2, 8, 14 Catalogue identifier of previous version: ADVL_v2_0 Journal reference of previous version: Comput. Phys. Comm. 175 (2006) 678 Does the new version supersede the previous version?: Yes Nature of problem: The programs compute the RHEED intensities during the growth of thin epitaxial structures prepared using the molecular beam epitaxy (MBE). The computations are based on the use of kinematical diffraction theory. Solution method: Epitaxial growth of thin films is modelled by a set of non-linear differential equations [1]. The Runge–Kutta method with adaptive stepsize control was used for solving initial value problem for non-linear differential equations [2]. Reasons for new version: According to the users' suggestions functionality of the program has been improved. Moreover, new use cases have been added which make the handling of the program easier and more efficient than the previous ones [3]. Summary of revisions: 1. The design pattern (See Fig. 2 of Ref. [3]) has been modified according to the scheme shown on Fig. 1. 2. A graphical user interface (GUI) for the program has been reconstructed. Fig. 2 presents a hybrid diagram of a GUI that shows how onscreen objects connect to use cases. 3. The program has been compiled with English/USA regional and language options. Note: The figures mentioned above are contained in the program distribution file. Unusual features: The program is distributed in the form of source project GROWTH06_v2.dpr with associated files, and should be compiled using Borland Delphi compilers versions 6 or latter (including Borland Developer Studio 2006 and Code Gear compilers for Delphi). Additional comments: Two figures are included in the program distribution file. These are captioned 1. Static classes model for Transaction design pattern. 2. A model of a window that shows how onscreen objects connect to use cases. Running time: The typical running time is machine and user-parameters dependent.