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 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 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 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: An apparatus, program product and method support the deallocation of a data structure in a multithreaded computer without requiring the use of computationally expensive semaphores or spin locks. Specifically, access to a data structure is governed by a shared pointer that, when a request is received to deallocate the data structure, is initially set to a value that indicates to any thread that later accesses the pointer that the data structure is not available. In addition, to address any thread that already holds a copy of the shared pointer, and thus is capable of accessing the data structure via the shared pointer after the initiation of the request, all such threads are monitored to determine whether any thread is still using the shared pointer by determining whether any thread is executing program code that is capable of using the shared pointer to access the data structure.

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 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: Methods, systems, and articles of manufacture for replacement of a failing processor of a multi-processor system running at least one operating system are provided. In contrast to the prior art, the replacement may be performed by system firmware without intervention by the operating system (i.e., the replacement may be transparent to the operating system). For some embodiments, the multi-processor system may be logically partitioned and the methods may be utilized to replace one or more shared or dedicated processors assigned to a logical partition, transparent to an operating system running on the partition.

Abstract: An apparatus, program product and method accommodate conventional yield calls within a multithreaded processor environment by coordinating yielding threads within the hypervisor. A hypervisor coordinates the yielding threads within the hypervisor to ensure all threads on a multithreaded processor execute within the same partition or hypervisor.

Abstract: A method, apparatus, system, and signal-bearing medium that in an embodiment set a resource indicator to indicate that a processor is using a resource in a logically-partitioned electronic device, determine whether a current partition in the logically-partitioned electronic device owns the resource, and clear the resource indicator after the processor is done using the resource. When a partition gives up ownership of a resource, a resource ownership state is changed to indicate that the partition does not own a resource, and the partition waits to continue executing until other processors have cleared their respective resource indicators. In an embodiment, the resource indicator is in a cache line that is local to the processor, which allows resources to be dynamically allocated with improved performance.

Abstract: Diagnostic data, such as a time increment corresponding to how long a thread waits to access a shared resource, is stored within a predetermined location in a data structure, such as a hash bucket in a hash table. The location is preferably correlated to the resource such that a display of the diagnostic data may be tailored to reflect a user-specified relationship between the data and resource.

Abstract: A logical partition debugger allows debugging one logical partition in a computer system without requiring the shutdown of other logical partitions. The logical partition debugger is implemented in software in the partition manager. The logical partition debugger provides many common debug functions known in existing hardware and software debuggers, but does so in a manner that only the partition being debugged is affected.

Abstract: A system, computer program product and method of logically partitioning a multiprocessor system are provided. The system is first partitioned into a plurality of partitions and each partition is assigned a percentage of the resources of the system. However, to provide the system with virtual machine capability, virtual resources, rather than physical resources, are assigned to the partitions. The virtual resources are mapped and bound to the physical resources that are available in the system. Because of the virtual machine capability of the system, logical partitions that are in need of resources that are assigned to other partitions are allowed to use those resources if the resources are idle.

Abstract: A resource and partition manager includes a power on/power off mechanism that is used to assure a hardware resource is powered down when control of the resource is removed from a logical partition, and to assure the hardware resource is powered up when control of the hardware resource is transferred to a logical partition. In the alternative, the resource and partition manager may simply place the hardware resource in a power on reset state when the hardware resource is transferred to a logical partition. In this manner, when made available to a partition, the hardware resource is in a power-on reset state, which is the state typically expected by the logical partition.

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 hardware resources. The resource and partition manager uses the lock mechanism to obtain a lock on a hardware resource when transferring control of the hardware resource to a logical partition that is powering on and when removing the hardware resource from a logical partition that is powering off. The resource and partition manager uses the lock mechanism to remove control of a hardware resource from, or return control to, an operating logical partition in order to facilitate hardware service operations on that hardware resource or on the physical enclosure in which it is contained.

Abstract: A resource and partition manager virtualizes interrupts without using any additional hardware in a way that does not disturb the interrupt processing model of operating systems running on a logical partition. In other words, the resource and partition manager supports virtual interrupts in a logically partitioned computer system that may include share processors with no changes to a logical partition's operating system. A set of virtual interrupt registers is created for each virtual processor in the system. The resource and partition manager uses the virtual interrupt registers to process interrupts for the corresponding virtual processor. In this manner, from the point of view of the operating system, the interrupt processing when the operating system is running in a logical partition that may contain shared processors and virtual interrupts is no different that the interrupt processing when the operating system is running in computer system that only contains dedicated processor partitions.

Abstract: A task synchronization mechanism operates on a global lock that is shared between processors an on local locks that are not shared between processors. The local locks are processor-specific locks. Each processor-specific lock is dedicated to a particular processor in the system. When shared access to a resource is required, a processor updates its processor-specific lock to indicate the processor is sharing the resource. Because each processor-specific lock is dedicated to a particular processor, this eliminates a significant portion of the memory bus traffic associated with all processors reading and updating the same lock. When exclusive access to a resource is required, the requesting processor waits until the count of all processor-specific locks indicate that none of these processors have a lock on the resource. Once no processor has a lock on the resource, exclusive access to the resource may be granted.

Abstract: An apparatus, program product and method track concurrent uses of a computer program across a plurality of logical partitions in a logically partitioned computer, such that a decision as to whether to grant or deny a request to use the computer program in a particular logical partition may be made based upon whether the requested use, coupled with other uses in other logical partitions in the computer, would violate a concurrent use software license associated with the computer program. As such, the license restrictions of a concurrent use software license can be enforced on a logically partitioned computer regardless of the particular logical partitions within which a computer program executes.

Abstract: A processor allocation mechanism for a logically partitionable computer system allows an administrator to specify processing capability allocable to each partition as an equivalent number of processors, where the processing capability may be specified as a non-integer value. This processing capability value is unaffected by changes to the processing capability values of other partitions. The administrator may designate multiple sets of processors, assigning each physical processor of the system to a respective processor set. Each logical partition is constrained to execute in an assigned processor set, which may be shared by more than one partition. Preferably, the administrator may designate a logical partition as either capped, meaning that a partition can not use excess idle capacity of the processors, or uncapped, meaning that it can.

Abstract: A logical partition debugger allows debugging one logical partition in a computer system without requiring the shutdown of other logical partitions. The logical partition debugger is implemented in software in the partition manager. The logical partition debugger provides many common debug functions known in existing hardware and software debuggers, but does so in a manner that only the partition being debugged is affected.