Storage Technology Corporation

International Business Machines Corporation

Oracle International Corporation

Sun Microsystems, Inc.

Patrick James Tomsula

Michael Wayne White

Jeffrey A Andre

George A Rudeseal

Jay S Belsan

Robert J Raicer

Charles Patrick Schafer

David A Serls

Jeffrey Steven Laughlin

Michael Lesile Roy

Mogens H Pedersen

Keith Radebaugh

Barbara L Steele

Implementations of the present disclosure involve a system and/or method for storing one or more data files in an n-level directory tree of a data storage system. In general, the system and/or method computes an n-byte value from a data file name which is used to create a directory path in the data storage system, where parts of the n-byte value are used to form each directory name in the directory path. Storage and retrieval of a data file is performed by storing in or retrieving data files from the computed directory. In one embodiment, the calculated n-byte value is obtained by computing the value with a cyclic redundancy check (CRC) algorithm. Use of the CRC algorithm to compute the directory path provides a balanced set of directories and number of data files that is repeatable such that location and retrieval of the data file is accomplished without the need to search through each directory of the system.

File load balancing in an N-level directory tree of a data storage system

A continuous data protection system, and associated method, for point-in-time data recovery. The system includes a consistency group of data volumes. A support processor manages a journal of changes to the set of volumes and stores meta-data for the volumes. A storage processor processes write requests by: determining if the write request is for a data volume in the consistency group; notifying the support processor of the write request including providing data volume meta-data; and storing modifications to the data volume in a journal. The support processor receives a data restoration request including identification of the consistency group and a time for data restoration. The support processor uses the data volume meta-data to reconstruct a logical block map of the data volume at the requested time and directs the storage processor to make a copy of the data volume and map changed blocks from the journal into the copy.

Continuous data protection of block-level volumes

The invention transforms source data from a source platform to a target platform with a single copy. A data request signal is communicated from the target platform to the source platform and a location of the source data is determined in a disk subsystem supporting snapshot. The disk subsystem (i.e., a snapshot facility) copies the source data in raw form to one or more target disks designated by the target platform. The locations of the source data and the target disks are communicated to the target platform and the source data is read from the disk subsystem to transform the data to the target platform. The process starts from a request of an application resident within the target platform. One or more data management units can be used to determine source and target disk locations. Preferably, the source platform also communicates metadata to the target platform; and thus metadata, when available, is also copied via snapshot operations in the disk subsystem. The use of Snapshot creates a static copy to help ensure data integrity.

System and methods for transforming data from a source to target platform using snapshot

A method and system in accordance with the present invention provides additional addressable space on a disk for use by a host processor using a virtual data storage subsystem. The method and system includes defining at least one of a plurality of extended image devices on a disk and requesting an instant image to be addressed to an extended image device utilizing channel command words by a host processor. The method and system also includes reading the instant image utilizing commands, such as channel command words or common descriptor blocks, by the host processor. In a method and system in accordance with the present invention, a plurality of extended image devices are defined as extensions of a primary functional device. Data may be transferred between at least one of the plurality of extended images and the primary functional device, or between at least one of the plurality of extended image devices and another of the plurality of extended image devices. An advantage of a method and system in accordance with the present invention is the availability of additional addressable space which may be used by the host processor for accomplishing the subsystem's functions, such as the copying of track pointers. By extending the amount of addressable space, the host processor is alleviated from having to conduct a search for available space within a primary functional device whenever space on the device becomes scarce.

Method and system for providing additional addressable functional space on a disk for use with a virtual data storage subsystem

The MVS device backup system functions to enable the data processor to manage the device backup function of a disk data storage subsystem in a manner that minimizes the expenditure of data processor resources. This is accomplished by the MVS device backup system determining the source device volume on the data storage subsystem, the target device volume on the data storage subsystem and identifying the extent of both. The MVS device backup system then transmits data to the data storage subsystem, representative of the assignment of DASD full tracks from the source device location on the data storage subsystem as well as DASD full tracks from the target (backup) device location on the data storage subsystem. The data processor based MVS device backup system then uses ECAM channel programs to instruct the data storage subsystem to perform the device backup operation using snapshot track pointer copy operations. Upon conclusion of the device backup operation by the data storage subsystem, the MVS device backup system updates the meta data required to complete the device backup operation.

MVS device backup system for a data processor using a data storage

The DASD file system copy system functions to enable the data processor to manage the data file copy function of a disk data storage subsystem in a manner that minimizes the expenditure of data processor resources. This is accomplished by the DASD file system copy system determining the source location on the data storage subsystem, the target location on the data storage subsystem and identifying the extents of both. The DASD file system copy system then transmits data to the data storage subsystem, representative of the assignment of DASD full tracks from the source location on the data storage subsystem as well as DASD full tracks from the target location on the data storage subsystem. The data processor based DASD file system copy system then uses ECAM channel programs to instruct the data storage subsystem to perform the data file copy operation using snapshot track pointer copy operations. Upon conclusion of the data file copy operation by the data storage subsystem, the DASD file system copy system updates the meta data required to complete the data file copy operation.

DASD file copy system for a data processor using a data storage

The write notification during copy system functions to enable the data processor to manage the data file copy function of a disk data storage subsystem in a manner that minimizes the expenditure of data processor resources. This is accomplished by the write notification during copy system determining the source volume on the data storage subsystem, the target volume on the data storage subsystem and identifying the extents of both. The write notification during copy system then transmits data to the data storage subsystem, representative of the assignment of DASD full tracks from the source location on the data storage subsystem as well as DASD full tracks from the target location on the data storage subsystem. The data processor based write notification during copy system then uses ECAM channel programs to instruct the data storage subsystem to perform the data file copy operation using snapshot track pointer copy operations. Upon conclusion of the data file copy operation by the data storage subsystem, the write notification during copy system updates the meta data required to complete the data file copy operation and indicates whether the copy completed with/without any conflicting write operation against the source or target.

System for providing write notification during data set copy

This file server system appears to the host computer to be a plurality of data storage devices which are directly addressable by the host computer using the native data management and access structures of the host computer. The file server however is an intelligent data storage subsystem that defines, manages and accesses synchronized sets of data and maintains these synchronized sets of data external from the host computer system's data management facilities in a manner that is completely transparent to the host computer. This is accomplished by the use of the snapshot application data group that extends the traditional sequential data set processing concept of generation data groups.

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Arvada, CO, United States of America

Patrick James Tomsula