In this paper we examine the recovery time in a database system using a Write-Ahead log protocol, such as ARIES[9], under the assumption that the buffer replacement poicy is strict LRU. in particular, analytical equations for log read time, data I/O, log application, and undo processing time are presented. our initial model assumes a read/write ratio of one, and a unifrom access pattern. this is later generalized to include different read/write rations, as well as a ''hot set'' model (i.e. x% of the accesses go to y% of the data). we show that in the unifrom access model, recovery is dominated by data I/O cots, but under extreme hot-set conditions, this msy no longer be true. furthermore, since we driver analytical equations, recovery can be analyzed for any set of parameter conditions not discussed here.
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