We study the optimal design of a heterogeneous coded elastic computing (CEC) network where machines have varying relative computation speeds. CEC introduced by Yang et al. is a framework which mitigates the impact of elastic events, where machines join and leave the network. A set of data is distributed among storage constrained machines using a Maximum Distance Separable (MDS) code such that any subset of machines of a specific size can perform the desired computations. This design eliminates the need to redistribute the data after each elastic event. In this work, we develop a process for an arbitrary heterogeneous computing network to minimize the overall computation time by defining an optimal computation load, or number of computations assigned to each machine. We then present an algorithm to define a specific computation assignment among the machines that makes use of the MDS code and meets the optimal computation load.
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Topological Coded Distributed Computing
This paper considers the MapReducelike coded distributed computing framework originally proposed by Li et al., which uses coding techniques when distributed computing servers exchange their computed intermediate values, in order to reduce the overall traffic load. In their original model, servers are connected via an errorfree common communication bus allowing broadcast transmissions. However, this assumption is one of the major limitations for practical implementations since realworld data centers may have network topologies far more involved than a single broadcast bus. We formulate a topological coded distributed computing problem, where the computing servers communicate with each other through some switch network. By using a special instance of fattree topologies, referred to as tary fattree proposed by AlFares et al. which can be built by some inexpensive switches, we propose a coded distributed computing scheme to achieve the optimal maxlink communication load (defined as the maximum load over all links) over any network topology.
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 Award ID(s):
 1817154
 NSFPAR ID:
 10297775
 Date Published:
 Journal Name:
 GLOBECOM 2020  2020 IEEE Global Communications Conference
 Page Range / eLocation ID:
 1 to 6
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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