Christopher D. Carothers

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In this paper, we introduce a new Time Warp system called ROSS: Rensselaer’s Optimistic Simulation System. ROSS is an extremely modular kernel that is capable of achieving event rates as high as 1,250,000 events per second when simulating a wireless telephone network model (PCS) on a quad processor PC server. In a head-to-head comparison, we observe that(More)
In optimistic parallel simulations, state-saving techniques have traditionally been used to realize rollback. In this article, we propose <italic>reverse computation</italic> as an alternative approach, and compare its execution performance against that of state-saving. Using compiler techniques, we describe an approach to automatically generate reversible(More)
The largest-scale high-performance (HPC) systems are stretching parallel file systems to their limits in terms of aggregate bandwidth and numbers of clients. To further sustain the scalability of these file systems, researchers and HPC storage architects are exploring various storage system designs. One proposed storage system design integrates a tier of(More)
There has been rapid growth in demand for mobile communications over the past few years that has led to intensive research and development of complex PCS (personal communication service) networks. Capacity planning and performance modeling is necessary to maintain a high quality of service to the mobile subscriber while minimizing cost. Simulation is widely(More)
We present VOGUE, a new state machine that combines two separate techniques for modeling long range dependencies in sequential data: data mining and data modeling. VOGUE relies on a novel VariableGap Sequence mining method (VGS), to mine frequent patterns with different lengths and gaps between elements. It then uses these mined sequences to build the state(More)
n this paper we illustrate scalable parallel performance for the TimeWarp synchronization protocol on the L and P variants of the IBM BlueGene supercomputer. Scalable Time Warp performance for models that communicate a large percentage of the event population over the network has not been shown on more than a handful of processors. We present our design for(More)
There has been rapid growth in the demand for mobile communications over the past few years. This has led to intensive research and development efforts for complex PCS (personal communication service) networks. Capacity planning and performance modeling is necessary to maintain a high quality of service to the mobile subscriber while minimizing cost to the(More)
ÐTime Warp is an optimistic protocol for synchronizing parallel discrete event simulations. To achieve performance in a multiuser network of workstation (NOW) environment, Time Warp must continue to operate efficiently in the presence of external workloads caused by other users, processor heterogeneity, and irregular internal workloads caused by the(More)
A load dtstrzbution system IS proposed to enable a sangle Tame War program to execute m background, s reading E [ over a CO1ectzon of posstbly heterogeneous wor stat~ons (zncludmg mult~processor hosts), util~zmg whatever otherwtse unused CPU cycles are avadable. The system uses a stmpleprocessor allocat~on policy to dynamical add or ~i delete hosts from(More)