Resumen:
A critical issue in large scale search engines is to e ciently
handle sudden peaks of incoming query tra c. Research in metric spaces
has addressed this problem from the point of view of creating caches that
provide information to, if possible, exactly/approximately answer a query
very quickly without needing to further process an index. However, one of
the problems of that approach is that, if the cache is not able to provide
an answer, the distances computed up to that moment are wasted, and
the search must proceed through the index structure. In this paper we
present an index structure that serves a twofold role: that of a cache and
an index in the same structure. In this way, if we are not able to provide
a quick approximate answer for the query, the distances computed up to
that moment are used to query the index. We present an experimental
evaluation of the performance obtained with our structure.
