International Business Machines Corporation

Cory G Smith

Paul Merril Greco

Erika Dawson

Scott Milton Fry

Gavin Stuart Johnson

Joel Kenneth Lyman

Jon Arthur Lynds

Ralph Thomas Beeston

Duke Andy Lee

Michael Ray Noel

In one embodiment, a product includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. An indicator of a physical position on the magnetic medium that corresponds to an end of the encrypted data is stored on the product. A product according to another embodiment includes a magnetic medium having written thereon data in a data track. The data includes encrypted data written over unencrypted data. A portion of the unencrypted data is located before the encrypted data on the medium. An indicator of a physical position on the magnetic medium that corresponds to a beginning of the encrypted data is stored on the product.

Monitoring of residual encrypted data to improve erase performance on a magnetic medium

In one embodiment, a system includes a processor and logic integrated with and/or executable by the processor, the logic being configured to: determine a physical position on a magnetic medium that corresponds to an end of an encrypted data set; store an indicator of the physical position on the magnetic medium and/or a memory coupled thereto; and cause obscuring of an unencrypted data set positioned after the physical position without overwriting the encrypted data set. In another embodiment, a computer program product includes a computer readable storage medium and program instructions embodied therewith, the program instructions readable and/or executable by the processor to cause the processor to: read an indicator of a physical position on a magnetic medium that corresponds to an end of an encrypted data set; and cause obscuring of an unencrypted data set positioned after the physical position without overwriting the encrypted data set.

In one embodiment, a system includes a processor, logic in the processor and/or memory configured to determine a physical position on a magnetic medium that corresponds to an end of encrypted data written over residual unencrypted data, and logic configured to store an indicator of the physical position on at least one of the magnetic medium and a memory coupled thereto. In another embodiment, a method includes determining a physical position on a magnetic medium that corresponds to an end of encrypted data written over residual unencrypted data, storing an indicator of the physical position on at least one of the magnetic medium and a memory coupled thereto.

A system according to one embodiment includes a processor; logic in the processor and/or a memory configured to determine a furthest physical position on a magnetic medium that unobscured data has been written to; and logic configured to store an indicator of the furthest physical position on at least one of the magnetic medium and a memory coupled thereto. A system according to another embodiment includes a processor; logic in the processor and/or a memory configured to receive an instruction to obscure data on a magnetic medium; logic configured to read an indicator of a furthest physical position on the magnetic medium that unobscured data has been written to; and logic configured to cause obscuring of the unobscured data on the magnetic medium, and terminating the obscuring upon reaching the physical position in the indicator.

Monitoring of extent of writing of unobscured data to improve erase performance on a magnetic medium

A system and method for performing a search operation within a sequential access data storage subsystem are disclosed. According to one embodiment, a data storage subsystem is provided which comprises a search module and a communication channel interface to communicatively couple the data storage subsystem to a host data processing system via a communication channel. In the described embodiment, the search module is configured to receive search attribute data from the host data processing system via the communication channel interface, where the search attribute data specifies a search attribute. The search module is further configured to perform a search operation on data of a sequential access storage element utilizing the search attribute and to provide search result data to the host data processing system via the communication channel interface in response to a performance of the search operation.

System and method for performing a search operation within a sequential access data storage subsystem

A read request of a sequential media from a host is executed with a read request data block size equal to a maximum recorded data block size parameter of the variable data block size storage device. Subsequently, if warranted, an adaptive read ahead data block size variable is set to equal a recorded data block size of data recorded on the sequential media that is responsive to the execution of the read request, and one or more read ahead requests of the sequential media are executed with a read ahead data block size equal to the adaptive read ahead data block size variable. The adaptive read ahead data block size variable is conditionally adjusted based on the recorded data block size(s) of data recorded on the sequential media that is responsive to the execution(s) of the read ahead request(s).

Growing community of inventors

Mesa, AZ, United States of America

Cory G Smith