+
+ - it might conceivably be useful to support a choice of indexing
+ strategies. The current "continuous index" mechanism' tradeoff of
+ taking O(N log N) space in order to be able to support any age
+ cutoff you like is not going to be ideal for everybody. A second
+ more conventional "discrete index" mechanism which allows the
+ user to specify a number of fixed cutoffs and just indexes each
+ directory on those alone would undoubtedly be a useful thing for
+ large-scale users. This will require considerable thought about
+ how to make the indexers pluggable at both index-generation time
+ and query time.
+ * however, now we have the cut-down version of the continuous
+ index, it might be the case that the space gain is no longer
+ worthwhile.