Probabilistic data locating in sparse data images

摘要

A set of probabilities may indicate the chance of finding the latest version of a data item in any particular data image layer of a data image. A client may use the set of probabilities to request the data item from one or more layers that have a higher probability of having that version of the data item. A client may query more recently created layers to determine whether they have a version of the data item. If any of the more recently created data image layers has a version of the data item, a client may request the data item from the most recent of the more recently created layers and may discard any data returned from the originally requested layer. A client may update the historical probabilities based on which layers contain versions of the data item.