Microsoft Corporation
Efficient clustered persistence

Abstract:

The systems and methods disclosed herein relate to using the clusters of a file to store versioning of a dataset. When the dataset is initially stored, a file is created that is twice the size of the dataset. The file may include one cluster (or a first set of clusters) that is marked as active and a second cluster (or a second set of clusters) that are marked inactive. The dataset is initially saved to the active cluster(s), and a version number is stored with the dataset. When the dataset is next saved, an application scans the file to determine whether there is (or are) an inactive cluster(s). If there is an inactive cluster(s) the second version of the dataset is saved to the inactive clusters. Both clusters are then marked active.