The present invention relates generally to the data processing field, and more particularly, relates to a method, system, and computer program product for implementing enhanced data storage in a removable media library to optimize performance and reliability.
An automated storage library or removable media library typically includes a plurality of storage bins or slots for retaining data storage media, such as magnetic tapes, magnetic disks, or optical disks, and includes a robotic picker mechanism for picking or gripping a cartridge containing the data storage medium and moving the cartridge between a storage position and an input output device or drive.
A media library device, such as an optical device, contains storage slots, drives, and a robotic arm that moves the two-sided media cartridges from the storage slots to the drives to be read and written. Each side of a cartridge is referred to as a volume. Each volume is stored on a single side of a two-sided cartridge. For example, volumes 1 and 2 reside on cartridge 1; volumes 3 and 4 reside on cartridge 2, and the like.
For many library devices, the drives can only read/write one side of the cartridge; therefore the robotic arm must flip the cartridge to read/write the other side. The process of moving a cartridge from a slot to a drive or flipping the cartridges already in a drive can take anywhere from 5-20 seconds depending on the model of library device.
Since a media library device provides random access to file data, performance inefficiencies can occur when the application/user is attempting to read or write data to both volumes on the same cartridge simultaneously. This could result in very slow response time as the media is continually flipped and flipped again to satisfy the requests. In some implementations movement of the media into the disk drives for reading or writing is managed so that users are unaware that it is not physically possible to read and write all media at the same time.
In some cases it may not be a coincidence that the user is accessing files on both volumes of the same cartridge. For example, the user application might unknowingly minor data to a second volume that happens to be on the other side. Often it is transparent to the user as to which physical cartridge the volumes are on.
A need exists for an efficient and effective mechanism for implementing improved data storage in a removable media library to optimize performance and reliability.
A principal aspect of the present invention is to provide a method, system and computer program product for implementing enhanced data storage in a removable media library to optimize performance and reliability. Other important aspects of the present invention are to provide such method, system, and computer program product substantially without negative effects and that overcome many of the disadvantages of prior art arrangements.
In brief, a method, system, and computer program product are provided for implementing enhanced data storage in a removable media library to optimize performance and reliability. When two volumes are initially formatted, user specified affinity information is used to identify an affinity between a first volume and a second volume for storing data. A user specified affinity type value is defined by the user specified affinity information. The first volume to be formatted is selected from a first removable media library (RML) and formatted. The second volume to be formatted is selected based upon an identified user specified affinity type value.
In accordance with features of the invention, the selected first volume and second volume enable enhanced data storage provided by the identified user specified affinity type value being selectively defined in a number of ways by the user.
In accordance with features of the invention, the user specified affinity information is used to intelligently select a plurality of unformatted cartridges and their location either in a single removable media library (RML) or in the location of the storage of a group of removable media libraries (RMLs).
In accordance with features of the invention, when the identified user specified affinity type value is a first affinity type, the second volume to be formatted is selected from a second removable media library (RML) than the first RML of the first volume. The second RML for the selected second volume is at a different physical location than the first RML, such as in a different building or a different city.
In accordance with features of the invention, when the identified user specified affinity type value is another affinity type, such as a second affinity type, the second volume to be formatted is selected from a second removable media library (RML) different than the first RML of the first volume. The second RML for the selected second volume is at the same physical location as the first RML.
In accordance with features of the invention, when the identified user specified affinity type value is another affinity type, such as a third affinity type, the second volume to be formatted is selected from a different cartridge in the same first RML.
The present invention together with the above and other objects and advantages may best be understood from the following detailed description of the preferred embodiments of the invention illustrated in the drawings, wherein:
In the following detailed description of embodiments of the invention, reference is made to the accompanying drawings, which illustrate example embodiments by which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the invention.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
In accordance with features of the invention, a method, system, and computer program product for implementing enhanced data storage in a removable media library to optimize performance and reliability.
Referring now to the drawings, in
Computer system 100 is shown in simplified form sufficient for understanding the present invention. The illustrated computer system 100 is not intended to imply architectural or functional limitations. The present invention can be used with various hardware implementations and systems and various other internal hardware devices, for example, multiple main processors.
As shown in
Various commercially available servers and commercially available computers can be used for computer system 100. CPU 102 is suitably programmed by the intelligent formatting program 142 and RML device selection control program 144 to execute the flowcharts of
Referring now to
Referring also to
Otherwise if the user specified affinity type is not equal to one, checking is performed for a user specified affinity type equal to two, which indicates for example, that the two volumes X and Y cannot reside at the same removable media library (RML) as indicated at a decision block 404. If the user specified affinity type equal to two is identified, then the second volume Y is selected from an unformatted pool of volumes in a different, second removable media library (RML) at the same location as the first removable media library (RML) as indicated at a block 406.
Otherwise if the user specified affinity type is not equal to two, as indicated at a decision block 408 checking is performed for a user specified affinity type equal to three, which indicates for example, that the two volumes X and Y cannot reside at the same cartridge. If the user specified affinity type equal to three is identified, then the second volume Y is selected from an unformatted pool of volumes in the same first removable media library (RML) from a different cartridge than the first volume X as indicated at a block 410.
Otherwise if the user specified affinity type is not equal to three, then as indicated at a decision block 412 checking is performed for a user specified affinity type equal to N, which indicates another user defined criteria. If the user specified affinity type equal to N is identified, then the second volume Y is selected from an unformatted pool of volumes in a defined removable media library (RML) based upon the defined criteria as indicated at a block 414.
The selected volume Y is formatted as indicated at a block 416. Then the sequential steps return as indicated at a block 418. Otherwise if the user specified affinity type is not equal to N, then an error is returned indicating an unknown affinity type as indicated at a block 420.
Referring now to
A sequence of program instructions or a logical assembly of one or more interrelated modules defined by the recorded program means 504, 506, 508, 510, direct the computer system 100 for implementing enhanced data storage in a removable media library to optimize performance and reliability of the preferred embodiment.
While the present invention has been described with reference to the details of the embodiments of the invention shown in the drawing, these details are not intended to limit the scope of the invention as claimed in the appended claims.