Abstract: Memory page de-duplication in a computer system that includes a plurality of virtual machine partitions managed by a hypervisor, where each virtual machine is assigned a different dedicated memory partition, may include: identifying, by the hypervisor, a plurality of identical memory pages in memory of one or more dedicated memory partitions; assigning, by the hypervisor, one of the identical memory pages as a master page; mapping, for each virtual machine having an identical memory page, each of the identical memory pages to the master page; and directing, by the hypervisor, reads of the memory page to the master page.

Abstract: A method, system, and computer readable medium to share data on a global basis within a symmetric multiprocessor (SMP) computer system are disclosed. The method may include grouping a plurality of processor cores into a plurality of affinity groups. The method may include creating hints about the global data in the plurality of group data structures. Each group data structure may correspond to an affinity group. The method may read a first group data structure by a thread executing on a processor core associated with a first affinity group.

Abstract: A method, system, and computer readable medium to share data on a global basis within a symmetric multiprocessor (SMP) computer system are disclosed. The method may include grouping a plurality of processor cores into a plurality of affinity groups. Global data may be copied into a plurality of group data structures. Each group data structure may correspond to an affinity group. The method may read a first group data structure by a thread executing on a processor core associated with a first affinity group.

Abstract: A method, system, and computer readable medium to share data on a global basis within a symmetric multiprocessor (SMP) computer system are disclosed. The method may include grouping a plurality of processor cores into a plurality of affinity groups. Global data may be copied into a plurality of group data structures. Each group data structure may correspond to an affinity group. The method may read a first group data structure by a thread executing on a processor core associated with a first affinity group.

Abstract: A method, system, and computer readable medium to share data on a global basis within a symmetric multiprocessor (SMP) computer system are disclosed. The method may include grouping a plurality of processor cores into a plurality of affinity groups. The method may include creating hints about the global data in the plurality of group data structures. Each group data structure may correspond to an affinity group. The method may read a first group data structure by a thread executing on a processor core associated with a first affinity group.

Abstract: In an embodiment, in response to receiving a completion interrupt for a first request from a resource, a determination is made whether relocation of memory contents accessed by performance of the first request is in progress. If the relocation of the memory contents accessed by performance of the first request is in progress, a second request is sent to the resource before the memory relocation completes. If the relocation of the memory contents accessed by the performance of the first request is not in progress, the completion interrupt for the first request is sent to the virtual machine that initiated the first request.

Abstract: In an embodiment, a request is received from a virtual machine that specifies a virtual ISN and a hardware resource. A physical ISN is selected that is assigned to the hardware resource. The physical ISN is assigned to the virtual ISN as an assigned pair. The request and the physical ISN are sent to the hardware resource. A physical interrupt is received from the hardware resource that specifies the physical ISN. In response to the receipt of the physical interrupt that specifies the physical ISN, the virtual machine and the virtual ISN that is assigned to the first physical ISN are determined from the physical interrupt and the assigned pair from among a plurality of virtual machines. In response to determining the virtual machine and first virtual ISN that is assigned to the physical ISN, a virtual interrupt that comprises that virtual ISN is sent to the virtual machine.

Abstract: A method of a computer system recovering from a core re-initialization failure is described. The method may include automatically detect a core re-initialization failure during a core re-initialization process by a hypervisor. The hypervisor automatically determines whether the core re-initialization failure is a permanent failure. If the core re-initialization failure is a permanent failure, then automatically determine, by the hypervisor, which cores are re-initialized and which cores are indeterminate. Automatically allocate the re-initialized cores between one or more virtual machines by the hypervisor.

Abstract: A method of a computer system recovering from a core re-initialization failure is described. The method may include automatically detect a core re-initialization failure during a core re-initialization process by a hypervisor. The hypervisor automatically determines whether the core re-initialization failure is a permanent failure. If the core re-initialization failure is a permanent failure, then automatically determine, by the hypervisor, which cores are re-initialized and which cores are indeterminate. Automatically allocate the re-initialized cores between one or more virtual machines by the hypervisor.

Abstract: In an embodiment, an average busy-to-success ratio is calculated for partitions that submitted operations to a shared resource during a first time period. A first busy-to-success ratio for a first partition during the first time period is calculated. If the first busy-to-success ratio is greater than the average busy-to-success ratio and a difference between the first busy-to-success ratio and the average busy-to-success ratio is greater than a threshold amount, a throttle amount for the first partition is increased. A first operation from the first partition during a first time subdivision of a second time period is received. If a number of operations received from the first partition during the first time subdivision of the second time period is greater than the throttle amount for the first partition, a busy indication is returned to the first partition and the first operation is not submitted to the shared resource.

Abstract: In an embodiment, in response to a request from a producer thread to set a bit in a global bitmap, a nodal lock is obtained on a nodal bitmap at a node at which the producer thread executes. A determination is made whether a corresponding bit in a pending clear bitmap in the nodal bitmap indicates that a clear of the bit in the global bitmap is pending. If the corresponding bit in the pending clear bitmap in the nodal bitmap indicates that a clear of the bit in the global bitmap is pending, the corresponding bit in the pending clear bitmap is cleared. If the corresponding bit in the pending clear bitmap in the nodal bitmap indicates that the clear of the bit in the global bitmap is not pending, a corresponding bit in a pending set bitmap in the nodal bitmap is set.

Abstract: In an embodiment, a request is received for a first partition to execute on a first virtual processor. If the first physical processor is available at a first node, the first virtual processor is dispatched to execute at the first physical processor at the first node that is the home node of the first virtual processor. If the first physical processor is not available, a determination is made whether the first physical processor is assigned to a second virtual processor and a home node of the second virtual processor is not the first node. If the first physical processor is assigned to a second virtual processor and the home node of the second virtual processor is not the first node, execution of the second virtual processor is stopped on the first physical processor and the first virtual processor is dispatched to the first physical processor.

Abstract: In an embodiment, a lock command is received from a thread that specifies a resource. If tier status in a nodal lock indicates the nodal lock is currently owned, an identifier of the thread is added to a nodal waiters list, and if the thread's lock wait indicator indicates that the thread owns the nodal lock, then a successful completion status is returned for the lock command to the thread after waiting until a next tier wait indicator in the nodal lock indicates that any thread owns a global lock on the resource. If the tier status indicates no thread holds the nodal lock, the tier status is changed to indicate the nodal lock is owned, and if a global waiters and holder list is empty, an identifier of a node at which the thread executes is added to the global waiters and holder list.

Abstract: In an embodiment, in response to a request from a producer thread to set a bit in a global bitmap, a nodal lock is obtained on a nodal bitmap at a node at which the producer thread executes. A determination is made whether a corresponding bit in a pending clear bitmap in the nodal bitmap indicates that a clear of the bit in the global bitmap is pending. If the corresponding bit in the pending clear bitmap in the nodal bitmap indicates that a clear of the bit in the global bitmap is pending, the corresponding bit in the pending clear bitmap is cleared. If the corresponding bit in the pending clear bitmap in the nodal bitmap indicates that the clear of the bit in the global bitmap is not pending, a corresponding bit in a pending set bitmap in the nodal bitmap is set.

Abstract: In an embodiment, an average busy-to-success ratio is calculated for partitions that submitted operations to a shared resource during a first time period. A first busy-to-success ratio for a first partition during the first time period is calculated. If the first busy-to-success ratio is greater than the average busy-to-success ratio and a difference between the first busy-to-success ratio and the average busy-to-success ratio is greater than a threshold amount, a throttle amount for the first partition is increased. A first operation from the first partition during a first time subdivision of a second time period is received. If a number of operations received from the first partition during the first time subdivision of the second time period is greater than the throttle amount for the first partition, a busy indication is returned to the first partition and the first operation is not submitted to the shared resource.

Abstract: In an embodiment, a request is received for a first partition to execute on a first virtual processor. If the first physical processor is available at a first node, the first virtual processor is dispatched to execute at the first physical processor at the first node that is the home node of the first virtual processor. If the first physical processor is not available, a determination is made whether the first physical processor is assigned to a second virtual processor and a home node of the second virtual processor is not the first node. If the first physical processor is assigned to a second virtual processor and the home node of the second virtual processor is not the first node, execution of the second virtual processor is stopped on the first physical processor and the first virtual processor is dispatched to the first physical processor.

Abstract: Dynamic control of memory affinity is provided for a shared memory logical partition within a shared memory partition data processing system having a plurality of nodes. The memory affinity control approach includes: determining one or more home node assignments for the shared memory logical partition, with each assigned home node being one node of the plurality of nodes of the system; determining a desired physical page level per node for the shared memory logical partition; and allowing the shared memory partition to run and using the home node assignment(s) and its desired physical page level(s) in the dispatching of tasks to physical processors in the nodes and in hypervisor page memory management to dynamically control memory affinity of the shared memory logical partition in the data processing system.

Abstract: Operating system-directed workload scheduling of an adjunct partition in a logically partitioned computer is selectively overridden to handle platform work requiring a Quality of Service (QoS) guarantee. Firmware may track outstanding requests for platform work for an adjunct partition, and in response to a request for platform work that requires a QoS guarantee, the firmware may assume or take over scheduling decisions for the adjunct partition from the operating system of an associated logical partition and schedule execution of the adjunct partition to ensure that the adjunct partition will be allocated sufficient execution resources to perform the platform work independent of the scheduling desires of the operating system. As a result, any platform work that potentially impacts the platform work of other adjunct partitions will not be held up as a result of an unwillingness or inability of the operating system to schedule execution of the adjunct partition.

Abstract: Hypervisor managed memory paging is provided in a data processing system having multiple logical partitions. The data processing system includes a shared memory pool defined within physical memory. The shared memory pool includes a volume of physical memory with dynamically adjustable sub-volumes or sets of physical pages associated with the multiple logical partitions. Each sub-volume or set is associated with a particular logical partition and includes mapped logical memory pages for that logical partition. A hypervisor memory manager interfaces the multiple logical partitions and the shared memory pool, and manages access to logical memory pages within the shared memory pool. The hypervisor memory manager further manages page-out and page-in of logical memory pages from the shared memory pool to one or more external paging devices. This page-out and page-in managing by the hypervisor memory manager is transparent to the multiple logical partitions.

Abstract: Relocating data in a virtualized environment maintained by a hypervisor administering access to memory with a Cache Page Table (‘CPT’) and a Physical Page Table (‘PPT’), the CPT and PPT including virtual to physical mappings. Relocating data includes converting the virtual to physical mappings of the CPT to virtual to logical mappings; establishing a Logical Memory Block (‘LMB’) relocation tracker that includes logical addresses of an LMB, source physical addresses of the LMB, target physical addresses of the LMB, a translation block indicator for each relocation granule, and a pin count associated with each relocation granule; establishing a PPT entry tracker including PPT entries corresponding to the LMB to be relocated; relocating the LMB in a number of relocation granules including blocking translations to the relocation granules during relocation; and removing the logical addresses from the LMB relocation tracker.