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10 Chakraborty et. al.
8 Future Directions and Conclusion
In this paper we show the effectiveness of pruning operation in an ICDB environment.
Without any pruning operation, the log file size increases in an unbounded manner with
time: a phenomenon that severely affects the update retrieval time. We present two
pruning algorithms considering clients with both uniform and widely varying MCIs. In
case of uniform MCIs, we show that the complete pruning algorithm curbs the linear
growth of the log file, and keeps this size within a bound. For varying MCIs among
clients, we show the effectiveness of the partial pruning algorithm in reducing the av-
erage update retrieval time for the clients. In this paper we consider only one log file.
However, in case of multiple update log files (i.e., one for each datagroup), these al-
gorithms can obviously be applied independently to each of the log files. There are a
few issues that need further investigation. First, a cost benefit analysis is necessary to
ascertain the period after which the update log files relevant to some lazy clients may be
deleted. Second, in the case of partial pruning, merging spawned files to further reduce
the latency needs to be studied.
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