Patent ID: 7146475
Filing Date: 2006-12-05
Classification: G06F,Y10S

Abstract:
1. A method for combining extents of a source data set, with minimal down time imposed on applications accessing the source data set, the source data set having a corresponding name, source DASD device(s) and one or more extent locations on the source DASD device(s), the method comprising the steps of: a) assessing the source data set to be migrated, the volume(s) it resides on, and the total space it occupies; b) allocating space for a corresponding target data set using the total source space as a primary allocation request and using the original source data set name; c) designating one or more target locations in the allocated space and assigning each source data set extent location to a respective one or more of the designated target locations; d) starting monitor programs on any images that can write to any of the identified source volumes in order to detect a subsequent change to the source data set; e) storing an indication of each source data set track detected by a monitor program as having changed; f) begin copying the source data set in accordance with said assignment of each source data set extent so as to form the corresponding target data set; g) while copying the source data set, periodically re-synchronizing source and target tracks detected by the monitor programs as having changed after having been previously copied; h) upon substantial completion of said copying, signaling an operator that closing the source data set is requested; i) recognizing that the source data set is closed thereby commencing a down time window; j) during the downtime window, finally re-synchronizing the source and target tracks detected by the monitor programs as having changed after having been previously copied; k) during the downtime window, accommodating any allocation changes affecting the source data set that occurred since the initial assessment of the source data set; l) changing catalog entries to reflect new target data set volumes; and m) signaling a user that the target data set may be opened, thereby terminating the down time window.