Abstract: A method, apparatus and computer program product are provided for implementing autonomous variation of media dismount time in a robotic media library. I/O requests to the robotic media library are monitored. Performance statistics are gathered for the I/O requests to the robotic media library. The gathered performance statistics are periodically checked to determine if a change is needed for the media dismount time. The gathered performance statistics include a media hit count of where a data storage medium (DSM) for an I/O request is in a robotic media drive, and a media near miss count where the DSM for the I/O request is in transit from the robotic media drive.

Abstract: An apparatus, program product and method utilize a cache payback parameter for selectively and dynamically disabling caching for potentially cacheable operations performed in connection with a memory. The cache payback parameter is tracked concurrently with the performance of a plurality of cacheable operations on a memory, and is used to determine the effectiveness, or potential payback, of caching in a particular implementation or environment. The selective disabling of caching, in turn, is applied at least to future cacheable operations based upon a determination that the cache payback parameter meets a caching disable threshold.

Abstract: A method, apparatus and article of manufacture for allocating use of an access device between a host operating system and a guest operating system. In one embodiment, a source of the received request to use the access device is determined as either the host operating system or the guest operating system. A determination of whether the host or guest operating system has a key for the access device is performed. The key enables either the host operating system or the guest operating system to use the access device. A determination of whether the received request is an altering request to change a state of the access device or a passive request to read the access device is also performed. The processing of the request from the host and guest operating systems is similar except when the request is an altering request and neither the host operating system nor the guest operating system has the key.

Abstract: Disclosed is a system, method, and program for processing an input file in a file system, wherein the input file has an input file name. A function is applied to map the input file name to a value. A data structure is processed to determine whether there is a preexisting file in the file system having a name that maps, according to the function, to the same value to which the input file name maps. Two files that map to a same value according to the function are capable of having a same name.

Abstract: A method, apparatus and article of manufacture for copying information from a first storage medium to a second storage medium. A first storage medium of memory blocks is mapped into at least one data block and at least one directory block. Two passes of the first storage medium are then performed. In the first pass, each data block is copied from the first storage medium to the second storage medium. If a read error occurs while copying a data block, a location of the data block and a data file stored in the data block are identified to provide future error handling capability. In the second pass, each directory block is copied from the first storage medium to the second storage medium.

Abstract: An apparatus, program product and method utilize a cache payback parameter for selectively and dynamically disabling caching for potentially cacheable operations performed in connection with a memory. The cache payback parameter is tracked concurrently with the performance of a plurality of cacheable operations on a memory, and is used to determine the effectiveness, or potential payback, of caching in a particular implementation or environment. The selective disabling of caching, in turn, is applied at least to future cacheable operations based upon a determination that the cache payback parameter meets a caching disable threshold.

Abstract: A method, apparatus and article of manufacture for allocating use of an access device between a host operating system and a guest operating system. In one embodiment, a source of the received request to use the access device is determined as either the host operating system or the guest operating system. A determination of whether the host or guest operating system has a key for the access device is performed. The key enables either the host operating system or the guest operating system to use the access device. A determination of whether the received request is altering request to change a state of the access device or a passive request to read the access device is also performed. The processing of the request from the host and guest operating systems is similar except when the request is an altering request and neither the guest operating system nor the guest operating system has the key.

Abstract: A method, apparatus and article of manufacture for copying information from a first storage medium to a second storage medium. A first storage medium of memory blocks is mapped into at least one data block and at least one directory block. Two passes of the first storage medium are then performed. In the first pass, each data block is copied from the first storage medium to the second storage medium. If a read error occurs while copying a data block, a location of the data block and a data file stored in the data block are identified to provide future error handling capability. In the second pass, each directory block is copied from the first storage medium to the second storage medium.