Abstract: A method includes determining, by a processor, whether a program check condition exists. The method further includes determining, by the processor, whether a lock descriptor of a lock in a file lock table satisfies an unlocking condition. The method further includes releasing, by the processor, the lock by setting the lock descriptor's host identifier as zero. The method further includes determining, by the processor, whether any lock in the file lock table satisfies a lock conflict condition. The method further includes determining, by the processor, whether the file lock table includes any lock descriptor that satisfies a locking condition. The method further includes creating, by the processor, a new lock using the lock descriptor that satisfies the locking condition.

Abstract: A method includes determining, by a processor, whether a program check condition exists. The method further includes determining, by the processor, whether a lock descriptor of a lock in a file lock table satisfies an unlocking condition. The method further includes releasing, by the processor, the lock by setting the lock descriptor's host identifier as zero. The method further includes determining, by the processor, whether any lock in the file lock table satisfies a lock conflict condition. The method further includes determining, by the processor, whether the file lock table includes any lock descriptor that satisfies a locking condition. The method further includes creating, by the processor, a new lock using the lock descriptor that satisfies the locking condition.

Abstract: A legacy operating system (OS) of a type generally associated with an enterprise-level, legacy data processing platform such as a mainframe is instead provided on a commodity data processing platform such as a personal computer. The legacy OS is adapted to communicate with legacy IOP devices of the type generally associated with the legacy platform to provide data protection mechanisms for legacy data. To initiate an I/O operation, a commodity OS executing on the commodity platform allocates a memory buffer and provides the virtual buffer address to the legacy OS. The legacy OS uses this address to construct a description of an I/O operation to be performed using the buffer. The description is then translated from one referencing a first memory page size in virtual address space into a description referencing a different page size in physical address space so that legacy IOP can complete the operation.

Abstract: An apparatus for and method of implementing a cluster lock processing system having a relatively large number of commodity cluster instruction processors which are managed by a highly scalable, off the shelf communication processor. Because the commodity processors have virtually no system viability features such as memory protection, failure recovery, etc., the communication processor assumes the responsibility for providing these functions. The low cost of the commodity cluster instruction processors makes the system almost linearly scalable. Furthermore, having a fully scalable communication processor ensures a completely scalable system. The cluster/locking, caching, and mass storage accessing functions are fully integrated into a single hardware platform.

Abstract: A system and method for processing I/O requests in a computing system. I/O packets are created via an operating system associated with the computing system, where the I/O packets include I/O transaction information. The I/O packets are made accessible to an I/O system. A command for a channel type connecting a target I/O component to the I/O system is constructed, where this command construction is based on the I/O transaction information provided in the I/O packet, and based on physical aspects of the target I/O component and channel type provided independently of the I/O packet. The constructed command is issued to the target I/O component in accordance with the channel type.

Abstract: A disk cache translation system for mapping data record lengths between systems having different data record lengths. Command queue (315) maps into initiation queue (305) to allow I/O manager (230) to manage I/O requests from operating system (125). I/O requests are statused by I/O manager (230) using status queue (325). Store-thru cache (280) provides a single interface to disk array (270) such that disk array write operations are reported complete only when user memory (250), I/O cache (280) and disk array (270) are synchronized. Data record length translations are performed using I/O cache (280) in order to align data record length differences between operating system (125) and I/O device (270).