Design and Implementation of a Contention-aware Coscheduling Strategy on Multi-Programmed Heterogeneous Clusters

Coscheduling has been gained a resurgence of interest as an effective technique to enhance the performance of parallel applications in multi-programmed clusters. However, existing coscheduling schemes do not adequately handle priority boost conflicts, leading to significantly degraded performance. To address this problem, in our previous study, we devised a novel algorithm that reorders the scheduling sequence of conflicting processes based on the rescheduling latency of their correspondents in remote nodes. In this paper, we exhaustively explore the design issues and implementation details of our contention-aware coscheduling scheme over Myrinet-based cluster system. We also practically analyze the impact of various system parameters and job characteristics on the performance of all considered schemes on a heterogeneous Linux cluster using a generic coscheduling framework. The results show that our approach outperforms existing schemes (by up to 36.6% in avg. job response time), reducing both boost conflict ratio and overall message delay

Cellular-Automaton-Based Node Scheduling Control for Wireless Sensor Networks

Wireless sensor networks (WSNs) generally consist of densely deployed sensor nodes that depend on batteries for energy. Having a large number of densely deployed sensor nodes causes energy waste and high redundancy in sensor data transmissions. The problems of power limitation and high redundancy in sensing coverage can be solved by appropriate scheduling of node activity among sensor nodes. In this paper, we propose a cellular automata (CA)-based node scheduling algorithm for prolonging network lifetime with a balance of energy savings among nodes while achieving high coverage quality. Based on a CA framework, we propose a new mathematical model for the node scheduling algorithm. The proposed algorithm uses local interaction based on environmental state signaling for making scheduling decisions. We analyze the system behavior and derive steady states of the proposed system. Simulation results show that the proposed algorithm outperforms existing protocols by providing energy balance with significant energy savings while maintaining sensing coverage quality

A Dual Control Approach for Indirect Configuration Propagation with Energy-Efficient Scheduling in Multi-agent Networking Systems

This paper presents a dual control approach for indirect system configuration propagation with energy-efficient agent scheduling. The proposed method influences the MNS (Multi-agent Networking Systems) operation by indirectly propagating the system configuration within the framework of local rules. Also, the proposed method adapts agent’s operational state according to the convergence rate of configuration propagation in order to balance energy consumption among agents in the MNS. Finally, we propose an optimal timing control for sequent input. Using the operation state control model, the gateway agent determines the optimal timing to give next input based on the value of the operation state. Simulation results are performed to demonstrate the superiority of the proposed method and we observe that the proposed scheme is less susceptible to error and shows more robust performance than the consensus method in an error-prone environment

Adaptive Duty Cycle Control with Queue Management in Wireless Sensor Networks

This paper proposes a control-based approach to the duty cycle adaptation for wireless sensor networks. The proposed method controls the duty cycle through the queue management to achieve high-performance under variable traffic rates. To have energy efficiency while minimizing the delay, we design a feedback controller, which adapts the sleep time to the traffic change dynamically by constraining the queue length at a predetermined value. In addition, we propose an efficient synchronization scheme using an active pattern, which represents the active time slot schedule for synchronization among sensor nodes, without affecting neighboring schedules. Based on the control theory, we analyze the adaptation behavior of the proposed controller and demonstrate system stability. The simulation results show that the proposed method outperforms existing schemes by achieving more power savings while minimizing the delay

Automatic handover control for distributed load balancing in mobile communication networks

Inthispaper,weproposeanauto-tuningofmobilityalgorithminthemobilecommunicationsystemsasaloadbalancingself-optimizationusecase.Thispaperpresentsadistributedapproachinwhichthetrafficloadcanbebalancedsystematicallybyutilizingtheeffectiveloadinformationofneighboringcells.Theproposedloadbalancingschemedetectsaloadimbalanceinthenetworkandresolvestheproblemautomaticallybycontrollingthehandoverparameterasanonlinearfunctionoftheloaddifference.Basedoncontroltheory,weanalyzetheadaptivebehavioroftheproposedcontrollerandderiveconditionforsystemstability.Resultsfromasymptoticanalysisandsimulationindicatethattheproposedlocalcontrollerofeachindividualcelleffectivelyachievestheglobalproperties,suchthattheloaddifferenceinthenetworkisstabilizedgloballywithinapredeterminedthreshold.Extensivesimulationresultsalsoshowthattheproposedschemeoutperformstheexistingmethodsbyreducingcallblockingrateoftheoverloadedcells

An efficient implementation of virtual interface architecture using adaptive transfer mechanism on myrinet

학위논문(석사) - 한국과학기술원 : 전산학전공, 2001.2, [ [iv], 52 p. ]한국과학기술원 : 전산학전공

암묵적 동시 스케쥴링에서 우선순위 높임 충돌을 해결하기 위한 효율적인 스케쥴링 기법에 관한 연구

학위논문(박사) - 한국과학기술원 : 전산학전공, 2007.2, [ viii, 80 p. ]The advent of fast networks and efficient user-level communication protocols has made clusters an attractive alternative to traditional multiprocessor systems. Due to the incremental scalability, cost-effectiveness and high-availability, cluster systems have recently gained increased acceptance as general-purpose multi-programmed computing servers for a variety of scientific and business applications. These applications are generally composed of multiple processes running on distinct CPUs that communicate frequently. Due to the synchronization needs of such applications, performance is greatly hampered if their processes are not scheduled simultaneously on the CPUs. Implicit coscheduling (ICS) is a well-known technique to address this problem in multi-programmed clusters, however, traditional ICS schemes do not incorporate steps to adequately deal with priority boost conflicts, leading to significantly degraded performance. In this thesis, we propose the use of runtime difference in contention across nodes to provide more sophisticated coscheduling decisions in response to the conflicts. We also present a novel coscheduling scheme termed PROC (Process ReOrdering-based Coscheduling) that adaptively regulates the scheduling sequence of conflicting processes based on the rescheduling latency of their correspondents in remote nodes. We perform extensive simulation-based experiments using both synthetic and realistic workloads to analyze the performance of PROC compared to alternatives such as local scheduling, a widely used batch scheduling, gang scheduling, and existing ICS schemes. The results show that all ICS schemes commonly experience priority boost conflicts, and that the proposed PROC significantly outperforms other ICS alternatives (or batch scheduling) by up to 50.4% (or 72.5%) in the average job response time. This improvement is achieved by reducing wasted idle time and spinning time without sacrificing fairness. We also present a generic c...한국과학기술원 : 전산학전공