International Business Machines Corporation

Microsoft Technology Licensing, LLC

Kodak Limited

Michael G Lotz

Luis Felipe Cabrera

Arthur Ray Roberts

Leonard Corning Lahey

James R Carlock

Brian Eldred Trede

The present invention is directed to systems and methods for hierarchical storage management. A system manager specifies policies used to migrate and recall data from between the local and a remote storage while the system itself is afforded latitude in complying or violating these policies. As a violation of the migration policy, the system of the present invention pre-migrates data from local storage to remote storage prior to the time that a given file will become eligible for migration thereto. During pre-migration, data resides in both local and remote storage. Once the time for migration has arrived, local storage space may be freed bv simply deleting the data stored locally and retaining the data stored remotely. As part of the recall policy, data is delayed from returning to local storage from the remote storage unless an access request or a write command specifically requires that the data be returned. Mechanisms are disclosed to detect if I/O requests that occur after data has been pre-migrated but before the data has been migrated invalidate the pre-migration.

Systems and methods for migration and recall of data from local and remote storage

The data storage management system provides the capability to move and/or copy the placeholder files from one file server volume to another file server volume, even if the destination file server volume resides on a different file server. This is accomplished by the use of unique and immutable migration keys which are included in the placeholder entries to identify the location of the associated data file with absolute certainty. In addition, a duplicate copy of the placeholder catalog file is maintained in the system to prevent loss of file system integrity in the event that the active placeholder catalog file is corrupted. This placeholder data is maintained in a placeholder volume catalog which provides users with a file-system-like view of the placeholder files which reside on the selected volume.

Data storage management for network interconnected processors using

Use of a single pass print data stream conversion process when sufficient memory is available to store all the page data to be printed and reversion to a double pass conversion when insufficient memory is available. Scanning of the input data stream, storing the page data, and downloading the resource data to the printer continues so long as sufficient memory to store the page data is available. If the available memory is filled before the entire page is scanned, the stored page data is discarded. The scanning continues to download the resource data but the page data is no longer stored. When the page has been completely scanned, the scanning is restarted at the beginning of the page, downloading the page data to the printer and discarding the resource data during the second scan.

Fast printer data stream conversion with constrained memory

Growing community of inventors

Louisville, CO, United States of America

Michael G Lotz