Chuprat, Suriayati (2009) The deadlinebased scheduling of divisible realtime workloads on multiprocessor platforms. PhD thesis, Universiti Teknologi Malaysia, Faculty of Science.

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Abstract
Current formal models of realtime workloads were designed within the context of uniprocessor realtime systems; hence, they are often not able to accurately represent salient features of multiprocessor realtime systems. Researchers have recently attempted to overcome this shortcoming by applying workload models from Divisible Load Theory (DLT) to realtime systems. The resulting theory, referred to as Realtime Divisible Load Theory (RTDLT), holds great promise for modeling an emergent class of massively parallel realtime workloads. However, the theory needs strong formal foundations before it can be widely used for the design and analysis of realtime systems. The goal of this thesis is to obtain such formal foundations, by generalizing and extending recent results and concepts from multiprocessor realtime scheduling theory. To achieve this, recent results from traditional multiprocessor scheduling theory were used to provide satisfactory explanations to some apparently anomalous observations that were previously made upon applying DLT to realtime systems. Further generalization of the RTDLT model was then considered: this generalization assumes that processors become available at different instants of time. Two important problems for this model were solved: determining the minimum number of processors needed to complete a job by its deadline; and determining the earliest completion time for a job upon a given cluster of such processors. For the first problem, an optimal algorithm called MINPROCS was developed to compute the minimum number of processors that ensure each job completes by its deadline. For the second problem, a Linear Programming (LP) based solution called MIN� was formulated to compute the earliest completion time upon given number of processors. Through formal proofs and extensive simulations both algorithms have been shown to improve the nonoptimal approximate algorithms previously used to solve these problems.
Item Type:  Thesis (PhD) 

Additional Information:  Thesis (Ph.D (Matematik)) Universiti Teknologi Malaysia, 2009; Supervisor : Prof. Dr Shaharuddin Salleh 
Uncontrolled Keywords:  realtime workloads, multiprocessor realtime systems 
Subjects:  Q Science > QA Mathematics 
Divisions:  Science 
ID Code:  13589 
Deposited By:  Ms Zalinda Shuratman 
Deposited On:  17 Feb 2012 04:14 
Last Modified:  17 Feb 2012 04:24 
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