• Title/Summary/Keyword: OpenMP directive

Search Result 3, Processing Time 0.034 seconds

Improving the Calculation Speed of Ray-tracing Based Simulator for Analyzing an Integrating Sphere with OpenMP Directive and Guaranteeing the Randomness of Monte Carlo Method (광선추적법 기반의 적분구 분석 시뮬레이터에서 OpenMP 지시어를 이용한 속도 향상 및 몬테카를로 방법의 무작위성 보장)

  • Kim, Seung-Yong;Kim, Dae-Chan;O, Beom-Hoan;Park, Se-Geun;Lee, El-Hang;Lee, Seung-Gol
    • Korean Journal of Optics and Photonics
    • /
    • v.22 no.2
    • /
    • pp.83-89
    • /
    • 2011
  • In order to improve the calculation speed of an integrating-sphere simulator based on a ray-tracing method, parallel processing with OpenMP directive was implemented into the simulator and the randomness of Monte Carlo method was guaranteed by utilizing a parallel random number generator. It was confirmed that simulation results obtained with more than $10^7$ rays showed good agreement with theoretical results within the error range of 0.5%, and that the calculation speed improved as the number of threads increased. Finally, the spatial response distribution functions of a real integrating sphere were simulated and compared with previous results.

An Efficient Tool for Verifying Races in OpenMP Directive Programs without Interthread Synchronization (스레드 동기화가 없는 OpenMP 디렉티브 프로그램을 위한 효율적인 경합검증 도구)

  • Ha, Ok-Kyoon;Kang, Moon-Hye;Kim, Young-Joo;Jun, Yong-Ki
    • Journal of KIISE:Computing Practices and Letters
    • /
    • v.14 no.3
    • /
    • pp.301-305
    • /
    • 2008
  • Races must be detected for debugging OpenMP programs with directives, because they may cause unintended nondeterministic results of programs. Intel Thread Checker, an existing tool that can detects races, can not verify the existence of races and is often time-consuming and tends to require large space. To solve these problems, we developed a tool that verifies the existence of races using user requirements and analyzed model of programs. However, the tool does not have optimal performance in programs which have no synchronization for interthread coordination. This paper presents an optimal tool that applies the optimum labeling and protocol for program models without interthread coordination. For synthetic programs without interthread synchronization, the tool verifies races over 250 times faster than the previous tool on the average, even if the maximum parallelism increases in every case of which the number of total accesses are identical.