Abstract: A logically-partitioned computer, program product and method utilize a flexible and adaptable communication interface between a partition and a partition manager, which permits optimal handling of partition management operations such as state change operations and the like over a wide variety of circumstances. In particular, a partition is permitted to indicate, in connection with a request to perform a partition management operation, whether an asynchronous notification should be generated or suppressed in association with the performance of the partition management operation by a partition manager. As a result, asynchronous notifications are selectively generated in association with the performance of partition management operations based upon indications in the requests made by partitions for such operations.

Abstract: A resource and partition manager of the preferred embodiments includes a lock mechanism that operates on a plurality of locks that control access to individual I/O slots. The resource and partition manager uses the lock mechanism to obtain a lock on an I/O slot when transferring control of the I/O slot to a logical partition that is powering on and when removing the I/O slot from a logical partition that is powering off. The resource and partition manager uses the lock mechanism to remove control of an I/O slot from, or return control to, an operating logical partition in order to facilitate hardware service operations on that I/O slot or on the physical enclosure in which it is contained.

Abstract: A first logical partition in a first processing complex of a server cluster is operated at a first level of a software code. Software code in a second logical partition in the same processing complex is updated to a second level. Processing operations are assumed by the second logical partition operating at the second level of software code. Other embodiments are described and claimed.

Abstract: A resource and partition manager of the preferred embodiments includes a lock mechanism that operates on a plurality of locks that control access to individual I/O slots. The resource and partition manager uses the lock mechanism to obtain a lock on an I/O slot when transferring control of the I/O slot to a logical partition that is powering on and when removing the I/O slot from a logical partition that is powering off. The resource and partition manager uses the lock mechanism to remove control of an I/O slot from, or return control to, an operating logical partition in order to facilitate hardware service operations on that I/O slot or on the physical enclosure in which it is contained.

Abstract: Processor time accounting is enhanced by per-thread internal resource usage counter circuits that account for usage of processor core resources to the threads that use them. Relative resource use can be determined by detecting events such as instruction dispatches for multiple threads active within the processor, which may include idle threads that are still occupying processor resources. The values of the resource usage counters are used periodically to determine relative usage of the processor core by the multiple threads. If all of the events are for a single thread during a given period, the processor time is allocated to the single thread. If no events occur in the given period, then the processor time can be equally allocated among threads. If multiple threads are generating events, a fractional resource usage can be determined for each thread and the counters may be updated in accordance with their fractional usage.

Abstract: An accounting method and multi-threaded processor include a mechanism for accounting for processor resource usage by threads within programs. Relative resource use is determined by detecting a particular cycle state of threads active within the processor. If instructions are dispatched for all threads or no threads, the processor cycle is accounted equally to all threads. Alternatively if no threads are in the particular cycle state, the accounting may be made using a prior state, or in conformity with ratios of the threads' priority levels. If only one thread is in the particular cycle state, that thread is accounted the entire processor cycle. If multiple threads are dispatching, but less than all threads are dispatching, the processor cycle is billed evenly across the dispatching threads.

Abstract: A method, apparatus, system, and signal-bearing medium that, in an embodiment, calculate a preemption credit for a partition if a virtual processor is preempted and the partition is unable to receive an entitled capacity of physical processor cycles during a dispatch window. The preemption credit is the portion of the entitled capacity that the partition is unable to receive. As long as the partition has a remaining preemption credit, in subsequent dispatch windows, a portion of the preemption credit is allocated to the virtual processor, and the preemption credit is reduced. In this way, in an embodiment, shared processor partitions may be ensured of receiving their entitled allocation of processor cycles.

Abstract: A method, system, and article of manufacture for processing virtual interrupts in a logically partitioned system are provided. An intelligent virtual global interrupt queue (virtual GIQ) that may be associated with a plurality of virtual processors running in a logical partition may be utilized. Upon receiving a virtual interrupt, the virtual GIQ may examine the operating states of the associated virtual processors. In an effort to ensure the virtual interrupt is processed as quickly as possible, the virtual GIQ may present the virtual interrupt to one of the associated virtual processors determined to be in an operating state best suited for processing the virtual interrupt.

Abstract: An apparatus and program product utilize a multithreaded processor having at least one hardware thread among a plurality of hardware threads that is capable of being selectively activated and deactivated responsive to a control circuit. The control circuit additionally provides the capability of controlling how an inactive thread can be activated after the thread has been deactivated, e.g., by enabling or disabling reactivation in response to an interrupt.

Abstract: A method, apparatus, and computer program product are disclosed in a data processing system for providing a virtualized time base in a logically partitioned data processing system. A time base is determined for each one of multiple processor cores. The time base is used to indicate a current time to one of the processor cores for which the time base is determined. The time bases are synchronized together for the processor cores such that each one of the processor cores includes its own copy of a synchronized time base. For one of the processor cores, a virtualized time base is generated that is different from the synchronized time base but that remains synchronized with at least a portion of the synchronized time base. The processor core utilizes the virtualized time base instead of the synchronized time base for indicating the current time to the processor core. The synchronized time bases and the portion of the virtualized time base remaining in synchronization together.

Abstract: A method utilizes a multithreaded processor having at least one hardware thread among a plurality of hardware threads that is capable of being selectively activated and deactivated responsive to a control circuit. The control circuit additionally provides the capability of controlling how an inactive thread can be activated after the thread has been deactivated, e.g., by enabling or disabling reactivation in response to an interrupt.

Abstract: A partition manager includes a resource detection mechanism that uses a persistent resource database to determine which resources were seen previously, and to determine which resources are required for a logical partition to start. Once all required resources for a logical partition are detected, the logical partition is started. In this manner, a logical partition may be started as soon as all of its resources are available, without waiting on the resources of other logical partitions. In addition, a missing required resource will prevent a logical partition from starting, thus avoiding the crash of a logical partition due to missing resources.

Abstract: A resource and partition manager of the preferred embodiments includes a lock mechanism that operates on a plurality of locks that control access to individual PCI adaptor slots. The resource and partition manager uses the lock mechanism to obtain a lock on an PCI adaptor slot when transferring control of the PCI adaptor slot to a logical partition that is powering on and when removing the PCI adaptor from a logical partition that is powering off. The resource and partition manager uses the lock mechanism to remove control of an PCI adaptor slot from, or return control to, an operating logical partition in order to facilitate hardware service operations on that PCI adaptor slot or on the physical enclosure in which it is contained.

Abstract: An apparatus and program product for coordinating the distribution of CPUs as among logically-partitioned virtual processors. A virtual processor may yield a CPU to precipitate an occurrence upon which its own execution may be predicated. As such, program code may dispatch the surrendered CPU to a designated virtual processor.

Abstract: An apparatus, program product and method for automatically and transparently determining the time required to migrate a logical partition. This determined latency may be used to update clocks and other time-related values of the migrated logical partition.

Abstract: An apparatus, program product and method for facilitating logical partition migrations between computers by determining if the firmware of the computers is compatible. A hypervisor of a source logical partition may transfer a token and compatibility table indicative of firmware running on the source computer. A hypervisor on the system of the target logical partition may compare the firmware indicated by the token with a token and/or compatibility table listing firmware versions compatible with the target computer. Conversely, a token of the target computer may be compared to a compatibility table associated with firmware that is compatible with the source computer. In either instance, a match may result in the migration of the logical partition. Alternatively, an absence of a match may result in the migration being prohibited.

Abstract: An apparatus, program product and method for tracking the state of a migrating logical partition. Embodiments may use the state to determine the readiness and/or appropriateness of a page of the logical partition for transferring. The state may include a value or other data used to track changes affecting the page or the relative ease and/or appropriateness of migrating the page. A page manager table with entries corresponding to the state of each page of the logical partition may be used to track the state while the logical partition continues to run during a migration.

Abstract: A partition migration mechanism migrates a logical partition executing an operating system and resumes the logical partition before all resources in the logical partition have been migrated. When a partition is being migrated, a call checkpoint mechanism creates checkpoints of the state of the operating system when the partition manager is called. Before performing the call to the partition manager, a check is made to determine if all resources required by the call are available. If so, the partition manager call is executed. If all resources required by the call are not available, a resource fault is indicated, which causes the operating system state from the last checkpoint to be restored and a corresponding virtual CPU to be preempted until the resource that caused the fault becomes available. Exceptions that do not require the missing resource may be performed while the virtual CPU awaits the resource to become available.

Abstract: An apparatus, program product and method for coordinating the distribution of CPUs as among logically-partitioned virtual processors. A virtual processor may yield a CPU to precipitate an occurrence upon which its own execution may be predicated. As such, program code may dispatch the surrendered CPU to a designated virtual processor.

Abstract: A partition manager includes an I/O reconfiguration mechanism and a logical partition suspend/resume mechanism that work together to perform autonomic I/O reconfiguration in a logically partitioned computer system. When I/O reconfiguration is required, the affected logical partitions are suspended, the I/O is reconfigured, and the affected logical partitions are resumed. Because the logical partitions are suspended during I/O reconfiguration, any ghost packet that may occur when the I/O is reconfigured is ignored.