Abstract: In a logically partitioned host computer system comprising host processors (host CPUs) partitioned into a plurality of guest processors (guest CPUs) of a guest configuration, a perform topology function instruction is executed by a guest processor specifying a topology change of the guest configuration. The topology change preferably changes the polarization of guest CPUs, the polarization related to the amount of a host CPU resource is provided to a guest CPU.

Abstract: An input/output subsystem is configured as a plurality of input/output subsystem images, each of which appears to a program as an independent input/output subsystem. An input/output subsystem image is identified by an input/output subsystem image identifier, which is used by various programs to designate the particular input/output subsystem image for which an I/O operation is to be performed. An input/output subsystem image includes, for instance, one or more input/output paths. An input/output path of an input/output subsystem image is identified by an input/output path identifier, as well as a physical input/output path identifier.

Abstract: Exemplary embodiments include a system and storage medium for managing computer processing functions in a multi-processor computer environment. The system includes a physical processor, a standard logical processor, an assist logical processor sharing a same logical partition as the standard logical processor, and a single operating system instance associated with the logical partition, the single operating system instance including a switch-to service and a switch-from service. The system also includes a dispatch component managed by the single operating system instance. Upon invoking the switch-to service by standard code, the switch-to service checks to see if an assist logical processor is online and, if so, it updates an integrated assist field of a work element block associated with the task for indicating the task is eligible to be executed on the assist logical processor. The switch-to service also assigns a work queue to the work element block.

Abstract: Exemplary embodiments include a method, system, and storage medium for managing computer processing functions in a multi-processor computer environment that includes a standard logical processor and an assist logical processor, each of which share the same operating system instance within a logical partition. The method includes invoking a switch-to service by standard code. The standard code is running on a standard logical processor and is executing a task. The switch-to service checks to see if an assist logical processor is online, and it if finds one, the switch-to service updates an integrated assist field of a work element block associated with the task and assigns a queue to the work element block. The task is dispatched, in accordance with business rules identified in a system control block, on either of said assist logical processor or said standard logical processor.

Abstract: A method is provided for determining whether a logical processor of an information processing system has access to an address space of the information processing system. An instruction is issued by a first processor, the instruction referencing a target logical processor and a target address space. In response to the instruction, first information is checked to determine whether the target logical processor is running. When it is determined that the target logical processor is not running, second information is checked by a host program to determine whether the target logical processor has access to the target address space.

Abstract: A method is provided for a first logical processor to determine a running status of a target logical processor of an information processing system. In such method, an instruction is issued by the first logical processor running on the information processing system for determining whether the target logical processor is running. In response to issuing the instruction, a state descriptor belonging to the target logical processor is queried to determine whether the target logical processor is currently running. A result is then returned to the first logical processor, the result indicating whether or not the target logical processor is currently running.

Abstract: An input/output subsystem is configured as a plurality of input/output subsystem images, each of which appears to a program as an independent input/output subsystem. An input/output subsystem image is identified by an input/output subsystem image identifier, which is used by various programs to designate the particular input/output subsystem image for which an I/O operation is to be performed. An input/output subsystem image includes, for instance, one or more input/output paths. An input/output path of an input/output subsystem image is identified by an input/output path identifier, as well as a physical input/output path identifier.

Abstract: Input/output (I/O) communications subadapters, such as subchannels, of an I/O subsystem are dedicated to components, such as I/O devices, of the I/O subsystem. The subadapters provide information about the associated components, in response to the execution of I/O instructions. To enhance I/O connectivity, a plurality of sets of I/O subadapters is provided to an operating system image. This allows programs of the operating system image to access a same component via different sets of I/O communications subadapters. Further, it enables an operating system image to use more than 64 k subchannels.

Abstract: A method and apparatus for managing the execution on guest processors of a broadcast instruction requiring a corresponding operation on other processors of a guest machine. Each of a plurality of processors on an information handling system is operable either as a host processor under the control of a host program executing on a host machine or as a guest processor under the control of a guest program executing on a guest machine. The guest machine is defined by the host program executing on the host machine and contains a plurality of such guest processors forming a guest multiprocessing configuration. A lock is defined for the guest machine containing an indication of whether it is being held by a host lock holder from the host program and a count of the number of processors holding the lock as guest lock holders. Upon decoding a broadcast instruction executing on a processor operating as a guest processor, the lock is tested to determine whether it is being held by a host lock holder.

Abstract: According to the present invention a method and a device is provided for concurrent removal of processor capacity from a running computer. The method and device may, e.g., be used for non-disruptive removal of processors from the enabled physical configuration without any involvement of the operating system. The computer comprises a resource controller configured to control a physical resource pool including the actual physical resources and a capacity virtualizer configured to provide multiple sets of virtual resources from a capacity virtualizer resource pool, whereby the provided sets of virtual resources allow to host independent operating systems concurrently.

Abstract: An input/output subsystem is configured as a plurality of input/output subsystem images, each of which appears to a program as an independent input/output subsystem. In response to an operating system image submitting an input/output (I/O) request requesting access to an input/output subsystem image, a determination is made as to whether the operating system image is authorized to access the input/output subsystem image. In response to the access being authorized, the I/O request is authorized.

Abstract: A communications adapter is shared by a plurality of input/output (I/O) subsystem images of an I/O subsystem of a central processing complex. To enable the sharing, the communications adapter is configured to a plurality of I/O paths of the plurality of I/O subsystem images. An I/O subsystem may have one or more shared communications adapters.

Abstract: In an environment employing a fabric, such as a cascading switch network, a predictable input/output (I/O) configuration is provided. The I/O configuration explicitly specifies the one or more peripheral units accessible by a program, such as an operating system. Other peripheral units not specified in the I/O configuration are not accessible, thus, providing a secure environment.

Abstract: An input/output subsystem of a computing environment is configured as a plurality of input/output subsystem images, each of which appears to a program as an independent input/output subsystem. An input/output subsystem image includes one or more communications adapters used for communicating within the computing environment. A communications adapter is identified by hardware of the computing environment by using a first identifier, and it is identified by a program of the computing environment by using a second identifier. The identifiers can be of different sizes.

Abstract: An input/output subsystem is configured as a plurality of input/output subsystem images, each of which appears to a program as an independent input/output subsystem. One or more input/output subsystem images of the plurality of input/output subsystem images are managed. An aspect of this management includes managing an input/output (I/O) configuration of an input/output subsystem image. This management may be performed dynamically.

Abstract: A method and apparatus for enforcing capacity limitations such as those imposed by software license agreements in an information handling system in which a physical machine is divided into a plurality of logical partitions, each of which is allocated a defined portion of processor resources by a logical partition manager. A software license manager specifies a maximum allowed consumption of processor resources by a program executing in one of the logical partitions. A workload manager also executing in the partition measures the actual consumption of processor resources by the logical partition over a specified averaging interval and compares it with the maximum allowed consumption. If the actual consumption exceeds the maximum allowed consumption, the workload manager calculates a capping pattern and interacts with the logical partition manager to cap the actual consumption of processor resources by the partition in accordance with the calculated capping pattern.

Abstract: Allocation of shareable resources of a computing environment are dynamically adjusted to balance the workload of that environment. Workload is managed across two or more partitions of a plurality of partitions of the computing environment. The managing includes dynamically adjusting allocation of a shareable resource of at least one partition of the two or more partitions in order to balance workload goals of the two or more partitions.

Abstract: Groups of partitions of a computing environment are managed. At least one group of the computing environment includes a plurality of partitions of the computing environment. Shareable resources are assigned to the partitions of the group and are managed as a group.

Abstract: An input/output subsystem is configured as a plurality of input/output subsystem images, each of which appears to a program as an independent input/output subsystem. An input/output subsystem image is identified by an input/output subsystem image identifier, which is used by various programs to designate the particular input/output subsystem image for which an I/O operation is to be performed. An operating system is provided with access to a plurality of input/output subsystem images of the input/output subsystem. One or more controls are provided to the operating system image to enable the operating system image to access the plurality of input/output subsystem images.

Abstract: A partitioned processing system capable of supporting diverse operating system partitions is disclosed wherein throughput information is passed from a partition to a partition resource manager. The throughput information is used to create resource balancing directives for the partitioned resource. The processing system includes at least a first partition and a second partition. A partition resource manager is provided for receiving information about throughput from the second partition and determining resource balancing directives. A communicator communicates the resource balancing directives from the partition manager to a kernel in the second partition which allocates resources to the second partition according to the resource balancing directives received from the partition manager.