The purpose of this paper is to report results of simulations of two algorithms for free space collection in log-structured storage systems. The algorithms considered are the age-threshold algorithm of Menon and Stockmeyer and the fitness algorithm of Butterworth. The simulations were done using a trace collected by Ruemmler and Wilkes from a file system over a period of two months. The performance of an algorithm is measured by the amount of disk I/O done as a result of free space collection. The performance of the algorithms and several variations of them are compared.
By: Larry Stockmeyer
Published in: RJ10222 in 2001
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