Unisys Corporation

Uniys Corporation

Michael J Rieschl

James F Merten

James R McBreen

Steven Bernardy

Douglas A Fuller

Carl R Crandall

Brian Garrett

Kurt N Johnson

Dave Q Anderson

Matthew E Trautman

Robert Louis Jacobs

Haeng D Park

David W Schroth

Mitch M Maurer

Michael C Otto

Laura M Nissen

Patrick W Cummings

Thomas N DeVries

Anne M Steiner

Edward Stafford

Kerry M Langsford

Linda J Brock

Max J Heimer

Warren N Stockton

Edward C Fisher

John Loberg

Qingyan Chen

Forest F Crocker

Lnda J Brock

Thomas J Bechtold

Systems and methods for obtaining access to database files in a computing system. A method may include receiving a first call from a database management system requesting access to a database file. The method may further include transmitting a second call to an operating system interface requesting that a memory-mapped data expanse file be created. The method may also include receiving a first address representing the database file in response to successful mapping of the database file to the memory-mapped data expanse file located at the operating system interface.

Data expanse using memory-mapped files on a system architecture interface layer-based mainframe operating system

A method includes retrieving, by a processor, a first entry from a global wait list as a current waiting lock. The method further includes decreasing, by the processor, a deadlock timer of the current waiting lock. The method further includes determining, by the processor, whether the deadlock timer equals zero. The method further includes appending, by the processor, the current waiting lock to an end of a deadlock victim selection list, if the deadlock timer equals zero. The method further includes selecting, by the processor, a victim from the deadlock victim selection list.

Systems and methods for implementing a multi-host record lock deadlock feedback mechanism

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.

Systems and methods for implementing a multi-host record lock mechanism

An apparatus includes a memory and a processor coupled to the memory. The processor is configured to perform the steps of: receiving a first head link for a page invalidation chain, the page invalidation chain including a plurality of page invalidation tables (PITs); receiving a second head link for an active real page table (RPT) chain, the active RPT chain including a plurality of RPTs; accessing a PIT, wherein the PIT includes a first data structure and a second data structure; invalidating the one or more RPTs, whereas the one or more RPTs are invalidated simultaneously in a batch; and releasing the one or more RPTs to a free RPT chain, the free RPT chain includes a plurality of released RPTs.

System and method for implementing an efficient large system page invalidation

Systems and methods for managing memory in a dynamic translation computer system are provided. Embodiments may include receiving an instruction packet and processing the instruction packet. The instruction packet may include one or more instructions for obtaining a block of virtual memory for use in an emulated operating environment from a slab of virtual memory in a host environment, maintaining a mapping between the block of virtual memory and physical memory when the block is returned to the host environment, and for filling the block of virtual memory with zeros and a pattern based, at least in part, on a detected fill type.

Systems and methods for memory management in a dynamic translation computer system

Systems and methods for obtaining access to a database file managed by an operating system in a computing system are disclosed. One method includes transmitting a call to an operating system from a database management system, the call requesting access to a database file. The method also includes receiving an address from the operating system at the database management system. The address represents a general address of the database file managed by the operating system. The method further includes transmitting a call to the operating system from the database management system, which includes an address and a size of a view of the database file to be created. The method also includes receiving an address of the view of the database file from the operating system.

Data expanse viewer for database systems

An apparatus for providing a computing environment in a computing system includes a first node, a second node, an operations server, and a communication link. The first node is capable of supporting a production computing environment and has a first disk storage. The second node is capable of supporting a second operational computing environment, independent of the production computing environment and has a second disk storage. The operations server manages the first and second node and can switch the production computing environment from the first node to the second node. The communications link allows communication between the first node, the second node, and the operations server. The second node can take over the production computing environment from the first node upon a failure of the first node by providing the second node with access to the first disk storage and rebooting the second node from the first disk storage. A method of switching a production computing environment from a first node, having a first disk storage, to a second node in the event of a failure on the first node includes determining if the first node had a failure and if the first node had a failure: reassigning ownership of the partition definition to the second node; restoring communications configuration on the second node; and booting the second node from the first disk storage.

System and method for providing a computer standby node

A method and apparatus for managing the configuration of a computing arrangement having a host operating system and an emulator operating system includes establishing host operating system interfaces to computing arrangement components. The computing arrangement is scanned, using the host operating system interfaces, to determine configuration information about computing arrangement components reserved for use by the emulator operating system. At least a portion of the scanned configuration information is communicated to the emulator operating system.

Configuration management for an emulator operating system

A method of and apparatus for efficiently managing video programming services by a provider of video on demand services in response to requests from cable television subscribers. The system is controlled by a multimedia application server. Upon receipt of a request, the multimedia application server searches for the most appropriate means of satisfying the request. If the requested program is already being provided, the streaming occurs from the same video server, if capacity is available. If the program already exists in streamable form, it is streamed from that location. If the requested program must be transferred to video server memory, the available space is found to accommodate the transfer or existing programming is swapped out.

Video-on demand video server disk/memory streaming selection methodology

A main memory simulation system includes storage files, a cache buffer, and an interface. The storage files includes both a fast look-up table and a slow look-up table. The fast look-up table is operable to directly obtain a page address that has been allocated to a main memory address while the slow look-up table is operable to first determine if a page address has been allocated to a main memory address and then to obtain the allocated page address. The interface operates to receive a request for transfer of main memory, in the form of a main memory address, from a storage file to the buffer of the cache. The interface responds by performing a page transfer between the storage file and buffer according to the page address that has been allocated to the requested main memory address, as found in the fast or slow look-up table.

Apparatus and method for the simulation of a large main memory address space given limited resources

A method of and apparatus for efficiently and effectively coupling a newly designed peripheral device to a legacy data processing system. The approach utilizes emulation of a SCSI tape device by a SCSI DVD device. Through device emulation, system-wide modifications are minimized.

Method and design for a DVD SCSI tape controller

A computer code debugging system. The computer code debugging system preferably includes a first computer and a second computer, but this is not required in all embodiments. The first computer may be, for example, a high performance mainframe system having hosting a simulator and debugger, and the second computer may be, for example, a lower cost generic personal computer or workstation that has superior graphic user interface (GUI) capabilities relative to the first computer. In some embodiments, the GUI on the second computer includes windows for displaying high level source code, corresponding computer machine language code, and/or corresponding machine code binary, as desired. The high level window and/or the computer machine language window may be used in some embodiments to interactively control the simulation of the machine code binary on the first computer, as desired.

Symbolic debug interface for register transfer simulator debugger

Emulation of a hardware peripheral is accomplished through use of object oriented software and runs in an object oriented environment. Particular adaptation of an emulation to enable specific data storage magnetic tape drive peripheral is described. Use of emulators in general enables continued reliance on legacy hardware and software without maintaining an entire suite of legacy hardware. Simplified emulation structure enabled by object oriented programming described herein makes migration from legacy systems feasible in stages at relatively low cost. In set-up and in use, users can have control over instances of emulator objects, including association with data files that operate as virtual storage media whether initially associated with the emulator or not, using a simple window-based interface for choosing particular data files, opening them, opening new instances of emulator objects and so forth. Variations are also described. Legacy programming is handled by use of legacy instructions communicated to the emulated object instances, which the object instances respond to appropriately.

Growing community of inventors

Roseville, MN, United States of America

Michael J Rieschl