Journal of KIISE:Computer Systems and Theory (한국정보과학회논문지:시스템및이론)

Korean Institute of Information Scientists and Engineers (한국정보과학회)
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A Scheme for Reducing File Access Latency with File Migration in Mobile Computing Environments

이동 컴퓨터 환경에서 파일 이주를 이용한 접근 지연 감소 기법

  • 한문석 (원주대학 행정전산과) ;
  • 박상윤 (성균관대학교 전기전자및컴퓨터공학부) ;
  • 엄영익 (성균관대학교 전기전자및컴퓨터공학부)
  • Published : 2001.12.01
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Abstract

We consider some problems of remote file accesses of multiple clients in mobile computing environments. In this environment, user mobility affects file access latency. Mobile hosts have severe resource constraints in terms of limited size of non-volatile storage. Thus, the burden of computation and communication load raise file access latency. In this paper, we propose a scheme for reducing the file access latency through the file migration. The objective is to minimize of file accesses for all mobile hosts which delivering the file to clients as quickly as possible. We develope an on-demand scheme which determines when the file server should migrate files to another server, or when it should transfer files to mobile hosts. Using simulation, we examine the effects which parameters such as file access frequency, file size, mobility rate have on file system access latency. Through simulation results, we show that our proposed migration scheme is effective in reducing the access latency on the requested file of a mobile host with high access rate and low mobility.

본 논문은 이동 컴퓨팅 환경에서 다중 이동 클라이언트를 위한 원격 파일 접근 문제를 다루었다. 이러한 환경에서 사용자의 이동성은 파일 접근에 영향을 미치며 이동 호스트는 제한된 용량의 비휘발성 저장 장치를 가진다는 점에서 자원에 대한 심각한 제약이 따른다. 따라서, 통신 및 연산 부하가 파일접근 지연을 야기할 수 있다. 본 논문은 이러한 문제를 해결하기 위하여 파일 이주 기법을 이용하여 접근 지연을 줄일 수 있는 기법을 제안한다. 이 기법의 목표는 모든 이동 호스트들에게 가능하면 신속하게 요청한 파일을 전달하여 접근지연을 최소화하는데 있다. 우리는 이동 호스트의 파일 요청이 있을 때 서버가 파일 이주를 결정하는 주문형 기법을 개발하였다. 시뮬레이션을 통하여 파일 접근 빈도, 파일 크기, 이동성 등이 파일시스템 접근 지연에 미치는 영향을 실험하였다. 시뮬레이션 결과에서 제안된 이주 기법은 파일 접근 빈도가 높고 이동성이 작은 이동 호스트가 요청한 파일에 대한 접근 지연을 줄이는데 효율적이라는 것을 보였다.

Keywords

References

  1. G. H. Forman, J. Zahorjan, 'The Challenges of Mobile Computing,' IEEE Computer, vol, 27 , No. 4, Apr. 1994 https://doi.org/10.1109/2.274999
  2. Laura Bright and Louiqa Raschid, 'Efficient Remote Data Access in a Mobile Computing Environment,' International Workshops on Parallel Processing, pp. 57-64, 2000 https://doi.org/10.1109/ICPPW.2000.869088
  3. James Griffioen, Todd A. Anderson and Yuri Breitbart, 'A Dynamic Migration Algorithm for a Distributed Memory-Based File Management System,' Proceedings of the IEEE Seventh International Workshop on Research Issues in Dam Engineering, pp. 151-160, 1997 https://doi.org/10.1109/RIDE.1997.583722
  4. S. Pope, 'Application Migration for Mobile Computers,' Proceedings of 3'rd International Workshop on Services in Distributed and Networked Environments, pp, 20-26, 1996 https://doi.org/10.1109/SDNE.1996.502443
  5. K.D. Levin, 'Adaptive Structuring of Distributed Databases,' Proceedings of the National Computer Conference, pp, 691-696, Jun. 1982
  6. W. W. Chu, 'Optimal File Allocation in a Multiple Computer System,' IEEE Transactions on Computer, C-18, 10, pp. 885-889, Oct. 1969 https://doi.org/10.1109/T-C.1969.222542
  7. R. G. Casey. ' Allocation of Copies of a File in a Information Network.' AFIPS SJCC. 40, pp. 617-625. 1972
  8. A. Segall. 'Dynamic File Assignment in a Computer Network,' IEEE Transactions on Automatic Control. AC-21,2, pp. 161-173, Apr. 1976 https://doi.org/10.1109/TAC.1976.1101193
  9. Q. Kurc, 'Optimization or File Migration in Distributed Systems,' Ph.D Thesis, Univ. of California, Berkeley. l988
  10. O.R. Lui Sheng, 'Models for Dynamic File Migration in Distributed Systems,' Ph.D Thesis, Univ. of Rochester, 1986
  11. A. Hac, 'A Distributed Algorithm for Performance Improvement Through File Replication, File Migration, and Process Migration,' IEEE Trans. Software Engineering, vol. 15. no. 11, pp. 1459-1470, 1990 https://doi.org/10.1109/32.41337
  12. R.T. Hurley, 'File Migration and File Replication: A Symbiotic Relationship,' IEEE Trans. on Parallel and Distributed Systems, vol. 7, no. 6, pp. 578-587, June 1996 https://doi.org/10.1109/71.506696
  13. R.T. Hurley, J.P. Black, and J.W. Wong, 'Limited Effects of Finite Storage on a Beneficial File Migration Policy,' Proc. 19th IEEE Conf. Local Computer Networks, PP. 132-139, Oct. 1994 https://doi.org/10.1109/LCN.1994.386576
  14. R.T. Hurley, SA. Yeap, J-W. Wong and J-P. Black. 'Potential Benefits of File Migration in a Heterogeneous Distributed File System,' Proc. ICCI '93 Fifth Int'l Conf, Computing and Information, pp. 123-127, May 1993 https://doi.org/10.1109/ICCI.1993.315393
  15. R.T Hurley, J.P. Black, and J.W. Wong, 'Performance of File Migration in a Distributed File Systems.' Proc, 10th International Conference on Computer Communications, pp. 685-692, Nov. 1990
  16. S. Khurana, A. Kahol, S. K. S. Gupta, and P. K Srimani, 'An Efficient Cache Maintenance Scheme for 'Mobile Environment:' Proceedings of the 20th Internarional Conference on Distributed Computing Systems, pp. 530-537, 2000 https://doi.org/10.1109/ICDCS.2000.840967
  17. K. W. Froese, 'File Cache Management for Mobile Computing,' MS Thesis, Dept. of Computer Science, Univ, of Saskatchewan, Canada, 1996
  18. T. M. Kroeger and D. D. E. Long,' Predicting File System Actions from Prior Events,' USENIX Conference Proceedings, pp. 319-328, Jan. 1996
  19. Subhasnini Rajagopalan and B. R. Badrinath, 'An Adaptive Location Management Strategy for Mobile IP,' Proceedings or the 1'st annual International Conference on Mobile Computing and Networking, pp. 170-180, 1995 https://doi.org/10.1145/215530.215572
  20. Averill M. Law and W. David Kelton, Simulation Modeling and Analysis, Second edition, McGraw-Hill 1991