POLLING, GREEDY AND HORIZON SERVERS ON A CIRCLE

成果类型:
Article
署名作者:
HAREL, A; STULMAN, A
署名单位:
St. John's University
刊物名称:
OPERATIONS RESEARCH
ISSN/ISSBN:
0030-364X
DOI:
10.1287/opre.43.1.177
发表日期:
1995
页码:
177-186
关键词:
摘要:
Service in a loop-based polling system consists of a single server moving around a closed tour, stopping to perform services wherever requests are encountered. There are N stations (unit buffer queues) spaced one unit of distance apart, and the server moves at a unit speed. All queues are identical, and the service time is deterministic. We compare the two well known cyclic polling and greedy servers with a new control policy called the horizon server. The cyclic polling server moves in one direction, even ii no requests are waiting, and stops whenever it encounters a request. The greedy server selects the nearest request for its next service. At any station the greedy server can reverse its direction ii a new request arrives nearby, and if no requests are waiting the greedy server does not move. The horizon server, with parameter d, ignores all requests for service from a distance farther than d. Within its horizon (less than or equal to d) it acts like the greedy server. Analytical solutions for N = 2 and 3 and numerical results for N less than or equal to 6 show that the horizon server, with the optimum value of d, outperforms the polling and the greedy servers.