• 제목/요약/키워드: Queues

검색결과 276건 처리시간 0.023초

우선순위 큐 성능 시험에 관한 연구 (A Study on the Runtime Test of Priority Queues)

  • 정해재
    • 정보처리학회논문지A
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    • 제17A권4호
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    • pp.167-172
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    • 2010
  • 본 논문에서는 우선순위 큐에 대한 성능 시험 모델을 제안하고, 제안된 모델에 따라 대표적인 우선순위 큐인 전통 힙, 후순위 힙, 및 페어링 힙의 성능 시험 결과를 보여준다. 이들 중 전통 힙이 분석된 시간복잡도에 있어서 최악인 것으로 알려져 있다. 그러나 제안된 성능 시험 모델에 근거한 성능 시험 결과에 따르면, 포인터를 사용하는 페어링 힙이 가장 느리고 전통 힙이 가장 빠른 것으로 나타났다. 두 묵시 힙에 대해서도, 분석된 시간복잡도로는 후순위 힙이 전통 힙보다 우수하지만, 성능 시험 결과는 반대인 것으로 나타났다.

단일 휴가형 Geo/Geo/1/K 대기행렬의 바쁜 기간 분석 (Busy Period Analysis of the Geo/Geo/1/K Queue with a Single Vacation)

  • 김길환
    • 산업경영시스템학회지
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    • 제42권4호
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    • pp.91-105
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    • 2019
  • Discrete-time Queueing models are frequently utilized to analyze the performance of computing and communication systems. The length of busy period is one of important performance measures for such systems. In this paper, we consider the busy period of the Geo/Geo/1/K queue with a single vacation. We derive the moments of the length of the busy (idle) period, the number of customers who arrive and enter the system during the busy (idle) period and the number of customers who arrive but are lost due to no vacancies in the system for both early arrival system (EAS) and late arrival system (LAS). In order to do this, recursive equations for the joint probability generating function of the busy period of the Geo/Geo/1/K queue starting with n, 1 ≤ n ≤ K, customers, the number of customers who arrive and enter the system, and arrive but are lost during that busy period are constructed. Using the result of the busy period analysis, we also numerically study differences of various performance measures between EAS and LAS. This numerical study shows that the performance gap between EAS and LAS increases as the system capacity K decrease, and the arrival rate (probability) approaches the service rate (probability). This performance gap also decreases as the vacation rate (probability) decrease, but it does not shrink to zero.

HPC environment Design and Implementation for Efficient Job Processing in an NEC system

  • 최지우;박정옥;김현중;양종원;하경주;서창호
    • 컴퓨터교육학회논문지
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    • 제13권4호
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    • pp.69-75
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    • 2010
  • As several users use a system simultaneously, a job management system is used to prevent exclusive uses in the system by a certain user and share entire resources for all users. The job management system is a type of scheduler that distributes limited resources for each job inquire efficiently. The system can be classified as different types and is to be properly selected according to the characteristics of systems and jobs. An NEC system is a job management system and usually applies NQS. The job management system has several queues, which are able to process jobs through distributed resources in which the efficiency of such job processing can be varied according to the composition of these queues. This study designs and configures differentiated queues according to service levels in order to improve the efficiency of the entire system as NQS is designed and that performs job processing. Also, this study analyze the performance of the job processing.

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이산사건 시뮬레이션에서의 효율적인 이벤트 리스트 관리를 위한 MList의 개선 방안 (An Improved MList for Efficient Event List Management in Discrete Event Simulation)

  • 김성곤;임동순
    • 한국시뮬레이션학회논문지
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    • 제18권4호
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    • pp.29-37
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    • 2009
  • 본 논문은 기존의 멀티 리스트 기반 엠리스트(MList)의 성능을 개선하기 위하여 동적 쉬프트 방식을 적용한 방법을 소개한다. 개선된 엠리스트는 일정한 수의 이벤트가 Tier 3에 쌓이게 되면 삭제 이벤트가 발생하지 않더라도 자동 쉬프트 작업을 통해 Tier 3에 저장된 이벤트들을 Tier 2의 새로운 칼렌다 큐로 이동시킨다. 즉, 기존에는 Tier 2에 하나의 칼렌다 큐가 있었으나, 개선된 방법에서는 다수의 칼렌다 큐가 동적으로 생성, 삭제된다. 이러한 동적 구조는 저장된 이벤트 수에 따라 적응력을 갖는 장점을 가져 성능측정 실험 결과 동적 쉬프트를 적용한 엠리스트는 기존의 엠리스트에 비해 20% 이상의 성능개선을 보였다.

위구르(회골, Uighur)기의 투르판(토노번,Trufan) 복식연구 (A study on the Turfan's costume in the period of Uighur)

  • 김소현
    • 한국의류학회지
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    • 제23권6호
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    • pp.829-840
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    • 1999
  • Ordinarily hair styles and headclothes show the racial characteristics. Uighur's men had let their long hair hang down their back in many queues, According to the order of estates men wore double high coronets hthree-pointed coronets from the headdress. Married women wore the felt headdress. The type of men's clothes were long caftans which had a round collar slits on the both sides and tight sleeves. They tied Chan Die belts and wore long boots. Women wore long tunics with everted collar which was decorated. Later the type of women's dress was changed into the long caftan. Late period of Turfan Uighur Mongol style had appeared.

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Development of Efficient Dynamic Bandwidth Allocation Algorithm for XGPON

  • Han, Man Soo;Yoo, Hark;Lee, Dong Soo
    • ETRI Journal
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    • 제35권1호
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    • pp.18-26
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    • 2013
  • This paper proposes an efficient bandwidth utilization (EBU) algorithm that utilizes the unused bandwidth in dynamic bandwidth allocation (DBA) of a 10-gigabit-capable passive optical network (XGPON). In EBU, an available byte counter of a queue can be negative and the unused remainder of an available byte counter can be utilized by the other queues. In addition, EBU uses a novel polling scheme to collect the requests of queues as soon as possible. We show through analysis and simulations that EBU improves performance compared to that achieved with existing methods. In addition, we describe the hardware implementation of EBU. Finally we show the test results of the hardware implementation of EBU.

A law of large numbers for maxima in $M/M/infty$ queues and INAR(1) processes

  • Park, Yoo-Sung;Kim, Kee-Young;Jhun, Myoung-Shic
    • Journal of the Korean Statistical Society
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    • 제23권2호
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    • pp.483-498
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    • 1994
  • Suppose that a stationary process ${X_t}$ has a marginal distribution whose support consists of sufficiently large integers. We are concerned with some analogous law of large numbers for such distribution function F. In particular, we determine a weak law of large numbers for maximum queueing length in $M/M\infty$ system. We also present a limiting behavior for the maxima based on AR(1) process with binomial thining and poisson marginals (INAR(1)) introduced by E. Mckenzie. It turns out that the result of AR(1) process is the same as that of $M/M/\infty$ queueing process in limit when we observe the queues at regularly spaced intervals of time.

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Fast Simulation of Overflow Probabilities in Multiclass Queues

  • Lee, Ji-Yeon;Bae, Kyung-Soon
    • Communications for Statistical Applications and Methods
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    • 제14권2호
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    • pp.287-299
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    • 2007
  • We consider a multiclass queue where queued customers are served in their order of arrival at a rate which depends on the customer type. By using the asymptotic results obtained by Dabrowski et al. (2006) we calculate the sharp asymptotics of the stationary distribution of the number of customers of each class in the system and the distribution of the number of customers of each class when the total number of customers reaches a high level before emptying. We also obtain a fast simulation algorithm to estimate the overflow probability and compare it with the general simulation and asymptotic results.