Abstract: A parallel computer system adds entropy to improve the quality of random number generation by using parity errors as a source of entropy because parity errors are influenced by external forces such as cosmic ray bombardment, alpha particle emission, and other random or near-random events. By using parity errors and associated information to generate entropy, the quality of random number generation in a parallel computer system is increased.

Abstract: An apparatus, program product and method utilize a barrier-based mechanism for arbitrating access to a shared resource in a massively parallel computer system. In a first processor among a plurality of processors in a massively parallel computer system, the number of times a barrier has been entered by processors in the massively parallel computer system in association with attempting to access the shared resource may be monitored, and the shared resource may be accessed by the first processor once the number of times the barrier has been entered matches a priority value associated with the first processor. As such, on massively parallel computer systems where potentially thousands of processors may attempt to concurrently access the same shared resource, the access by such processors may be coordinated in a logical fashion to reduce the risk of overwhelming the shared resource due to an excessive number of concurrent access attempts to the shared resource.

Abstract: A method for adding storage space to a server without powering down the server is provided. One embodiment provides a method for dynamically linking a storage space to a network server, comprising: adding a new disk drive image to a network server description for the network server through a host server operating system, the new disk drive image corresponding to the storage space to be linked; sending a dynamic linking request from the host server operating system to a network server operating system; in response to the dynamic linking request, sending a device scanning request from the network server operating system to the host operating system; in response to the device scanning request, requesting response from each device connected to each SCSI port of a host server and reporting the new disk drive image to the network server operating system; and presenting the new disk drive image to users connected to the network server.

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: Method and apparatus for controlling a plurality of storage devices connected to a host server system from a network server system are provided. One embodiment provides a method for controlling a plurality of devices connected to a host system, comprising: receiving, by an input/output processor (IOP) on a network server system, a device request from a network server operating system; determining to which one of the plurality of devices is the device request directed; creating a host system request for the one of the plurality of devices; and sending the host system request to an IOP of the host system. Another embodiment provides a medium containing program code that, when executed by a computer, causes the computer to perform a method for controlling a plurality of devices connected to a host system.

Abstract: A method for adding storage space to a server without powering down the server is provided. One embodiment provides a method for dynamically linking a storage space to a network server, comprising: adding a new disk drive image to a network server description for the network server through a host server operating system, the new disk drive image corresponding to the storage space to be linked; sending a dynamic linking request from the host server operating system to a network server operating system; in response to the dynamic linking request, sending a device scanning request from the network server operating system to the host operating system; in response to the device scanning request, requesting response from each device connected to each SCSI port of a host server and reporting the new disk drive image to the network server operating system; and presenting the new disk drive image to users connected to the network server.

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: Method and apparatus for controlling a plurality of storage devices connected to a host server system from a network server system are provided. One embodiment provides a method for controlling a plurality of devices connected to a host system, comprising: receiving, by an input/output processor (IOP) on a network server system, a device request from a network server operating system; determining to which one of the plurality of devices is the device request directed; creating a host system request for the one of the plurality of devices; and sending the host system request to an IOP of the host system. Another embodiment provides a medium containing program code that, when executed by a computer, causes the computer to perform a method for controlling a plurality of devices connected to a host system.

Abstract: An apparatus and method for testing object oriented software includes a software test framework that includes one or more test drivers and one or more testcases for each test driver. Each testcase can also have multiple variations. A TestDriver abstract class and a Testcase class are defined. Each test driver is created as an extension of the TestDriver class, and each testcase is created as an extension of the Testcase class, thereby promoting uniformity between different test drivers and between different test cases. When an instance of the TestDriver class is run, it instantiates its testcases, determines which variations of the testcases should be run, runs the variations, and reports the results. By providing the software test framework in the same programming environment in which the software under test is developed, the application programmer can program the needed tests without requiring the specialized skills of a test programmer.