275 results about "Virtual Processor" patented technology

A method of virtualizing memory through shadow page tables that cache translations from multiple guest address spaces in a virtual machine includes a software version of a hardware tagged translation look-aside buffer. Edits to guest page tables are detected by intercepting the creation of guest-writable mappings to guest page tables with translations cached in shadow page tables. The affected cached translations are marked as stale and purged upon an address space switch or an indiscriminate flush of translations by the guest. Thereby, non-stale translations remain cached but stale translations are discarded. The method includes tracking the guest-writable mappings to guest page tables, deferring discovery of such mappings to a guest page table for the first time until a purge of all cached translations when the number of untracked guest page tables exceeds a threshold, and sharing shadow page tables between shadow address spaces and between virtual processors.

A computer system includes at least one virtual machine that has a plurality of virtual processors all running on an underlying hardware platform. A software interface layer such as a virtual machine monitor establishes traces on primary structures located in a common memory space as needed for the different virtual processors. Whenever any one of the virtual processors generates a trace event, such as accessing a traced structure, then a notification is sent to at least the other virtual processors that have a trace on the accessed primary structure. In some applications, the VMM derives and maintains secondary structures corresponding to the primary structures, such as where the VMM converts, through binary translation, original code intended to run on a virtual processor into code that can be run on an underlying physical processor of the hardware platform. In these applications, the VMM may rederive or invalidate the secondary structures as needed upon receipt of the notification of the trace event. Different semantics are provided for the notification, providing different choices of performance versus guaranteed consistency between primary and secondary structures. In the preferred embodiment of the invention, a dedicated sub-system is included within the VMM for each virtual processor; each sub-system establishes traces, senses trace events, issues the notification, and performs other operations relating specifically to its respective virtual processor.

A virtual architecture and instruction set support explicit parallel-thread computing. The virtual architecture defines a virtual processor that supports concurrent execution of multiple virtual threads with multiple levels of data sharing and coordination (e.g., synchronization) between different virtual threads, as well as a virtual execution driver that controls the virtual processor. A virtual instruction set architecture for the virtual processor is used to define behavior of a virtual thread and includes instructions related to parallel thread behavior, e.g., data sharing and synchronization. Using the virtual platform, programmers can develop application programs in which virtual threads execute concurrently to process data; virtual translators and drivers adapt the application code to particular hardware on which it is to execute, transparently to the programmer.

This invention provides a computer system architecture and method for providing the same which can include a web page search node including a web page collection. The system and method can also include a web server configured to receive, from a given user via a web browser, a search query including keywords. The node is caused to search pages in its own collection that best match the search query. A search page returner may be provided which is configured to return, to the user, high ranked pages. The node may include a power-efficiency-enhanced processing subsystem, which includes M processors. The M processors are configured to emulate N virtual processors, and they are configured to limit a virtual processor memory access rate at which each of the N virtual processors accesses memory. The memory accessed by each of the N virtual processors may be RAM. In select embodiments, the memory accessed by each of the N virtual processors includes DRAM having a high capacity yet lower power consumption then SRAM.

Scheduling threads in a multi-threaded computer including selecting for awakening a thread that is waiting for a lock, the thread having an assigned virtual processor; determining whether the assigned virtual processor is running; and if the assigned virtual processor is not running, assigning the thread to run on another virtual processor. Selecting a thread may include selecting the thread according to thread priority or selecting the thread according to sequence of thread arrival in a wait queue. Selecting a thread may include selecting a thread having an assigned virtual processor that is running. Selecting a thread may include selecting a thread having an assigned virtual processor that is running and has at least a predetermined amount of time remaining in its current time slice.

The present invention is directed to making a guest operating system aware of the topology of the subset of host resources currently assigned to it. At virtual machine boot time a Static Resource Affinity Table (SRAT) will be used by the virtualizer to group guest physical memory and guest virtual processors into virtual nodes. Thereafter, in one embodiment, the host physical memory behind a virtual node can be changed by the virtualizer as necessary, and the virtualizer will provide physical processors appropriate for the virtual processors in that node.

In an embodiment, a device interrupt manager may be configured to receive an interrupt from a device that is assigned to a guest. The device interrupt manager may be configured to transmit an operation targeted to a memory location in a system memory to record the interrupt for a virtual processor within the guest, wherein the interrupt is to be delivered to the targeted virtual processor. In an embodiment, a virtual machine manager may be configured to detect that an interrupt has been recorded by the device interrupt manager for a virtual processor that is not currently executing. The virtual machine manager may be configured to schedule the virtual processor for execution on a hardware processor, or may prioritize the virtual processor for scheduling, in response to the interrupt.

Principles for enabling power management techniques for virtual machines. In a virtual machine environment, a physical computer system may maintain management facilities to direct and control one or more virtual machines executing thereon. In some techniques described herein, the management facilities may be adapted to place a virtual processor in an idle state in response to commands from a guest operating system. One or more signaling mechanisms may be supported such that the guest operating system will command the management facilities to place virtual processors in the idle state.

A multiple virtual processor (MVP) system using a special “YIELD” machine instruction inserted into a thread (virtual processor) at a selected point to trigger an immediate thread change (i.e., transfer of physical processor control to another thread). When the physical processor processes a YIELD instruction, the task thread surrenders control of the physical processor, and an otherwise idle thread is selected by a thread scheduling mechanism of the MVP system for loading into the physical processor. In one embodiment, the YIELD instruction includes an input operand that identifies the hardware signal on which the issuing thread intends to wait, and a result operand indicating the reason for reactivation.

The present invention provides a computer implemented method, data processing system, and computer program product for mapping and dispatching virtual processors in a data processing system having at least a first partition and a second partition. The data processing system runs a first partition on a virtual processor during a first timeslice. The data processing system identifies an at least one physical page used by the first partition and the second partition. The data processing system maps the at least one physical page to the first partition and the second partition. The data processing system determines a fitness value based on the mapping. The data processing system dispatches the Virtual processor to the second partition on a second timeslice based on the fitness value, wherein the second timeslice immediately succeeds after the first timeslice, whereby the at least one physical page remains in cache during at least the first timeslice and the second timeslice.

A sponge process, for example within a driver in a guest operating system, is associated in a virtual computer system with each virtual processor in one or more virtual machines. When timer interrupts become backlogged, for example because a virtual machine is temporarily descheduled to allow other virtual machines to run, and upon occurrence of a trigger event, a conventional interrupt is disengaged and catch-up interrupts are instead directed into an appropriate one of the sponge processes. The backlogged timer interrupts are thus delivered without unfairly attributing descheduled time to whatever processes happened to be running while the catch-up interrupts are delivered, and without violating typical guest operating system timing assumptions.

A virtualization apparatus includes one or more guest machines each comprised of a guest kernel and a guest user process, a hypervisor module installed in a host kernel and handling a request of the guest machine with regard to the virtualization apparatus, and a virtual processor supporting the guest machine to serve as a host user process and handling an interrupt and a switching of the guest machine, wherein address spaces of the guest kernel and the guest user process are designed to be separated from each other.

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.

The present invention provides a cluster load balancing method transparent to an operation system. Main functional modules comprise a load balancing module, a processor migrating module and a communication module. The method is characterized by comprising the following steps: 1, driving a virtual processor to migrate; 2, driving balance migration; 3, sending a migrating request to a target node and negotiating; 4, storing and restoring a state of the virtual processor; and 5, communicating. The method better solves the problem of low resource utilization rate of a cluster system. Along with the development of more popularization of the cluster system and the continuous development of hardware virtualization technology in the future, the method can be a good solution for the low resource utilization rate of the cluster system and has good application prospect.

Provided is a virtual computer system capable of finding a configuration whose total sum of memory access delays is smaller than that of a current configuration. In a virtual computer system in which with memory access times within a node and between nodes differing from each other, a hypervisor controls a plurality of virtual processors which execute a process on a plurality of nodes, the hypervisor includes a unit which obtains a total sum of memory access delay time on the virtual machine based on affinity information indicative of a latency or a band of communication between the virtual processors and traffic between the virtual processors, and a unit which reconfigures physical resources based on the total sum of delay time.

A heterogeneous processor architecture is described. For example, a processor according to one embodiment of the invention comprises: a first set of one or more physical processor cores having first processing characteristics; a second set of one or more physical processor cores having second processing characteristics different from the first processing characteristics; virtual-to-physical (V-P) mapping logic to expose a plurality of virtual processors to software, the plurality of virtual processors to appear to the software as a plurality of homogeneous processor cores, the software to allocate threads to the virtual processors as if the virtual processors were homogeneous processor cores; wherein the V-P mapping logic is to map each virtual processor to a physical processor within the first set of physical processor cores or the second set of physical processor cores such that a thread allocated to a first virtual processor by software is executed by a physical processor mapped to the first virtual processor from the first set or the second set of physical processors.

Administration of locks for critical sections of computer programs in a computer that supports a multiplicity of logical partitions that include determining by a thread executing on a virtual processor executing in a time slice on a physical processor whether an expected lock time for a critical section of the thread exceeds a remaining entitlement of the virtual processor in the time slice and deferring acquisition of a lock if the expected lock time exceeds the remaining entitlement.

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.

Methods and arrangements of assigning tasks to processors are discussed. Embodiments include transformations, code, state machines or other logic to detect an attempt to execute an instruction of a task on a processor not supporting the instruction (non-supporting processor). The method may involve selecting a processor supporting the instruction (supporting physical processor). In many embodiments, the method may include storing data about the attempt to execute the instruction and, based upon the data, making another assignment of the task to a physical processor supporting the instruction. In some embodiments, the method may include representing the instruction set of a virtual processor as the union of the instruction sets of the physical processors comprising the virtual processor and assigning a task to the virtual processor based upon the representing.

A method of virtual processing includes running a virtual processor (1), which when the virtual processor (1) encounters a faulting instruction unmaps the virtual processor (1) from the physical processor (A), and generates a list of other of the physical processors that could execute the instruction. Then determines if one of the other of the physical processors in the list is currently idle, and when one of the other of the physical processors in the list is determined to be currently idle, maps the virtual processor (1) to a physical processor (B) which is the one of the other of the physical processors in the list that was determined to be currently idle.

Hypervisor page fault processing logic is provided for a shared memory partition data processing system. The logic, responsive to an executing virtual processor of the shared memory partition data processing system encountering a hypervisor page fault, allocates an input/output (I/O) paging request to the virtual processor from an I/O paging request pool and increments an outstanding I/O paging request count for the virtual processor. A determination is then made whether the outstanding I/O paging request count for the virtual processor is at a predefined threshold, and if not, the logic places the virtual processor in a wait state with interrupt wake-up reasons enabled based on the virtual processor's state, otherwise, it places the virtual processor in a wait state with interrupt wake-up reasons disabled.

A next-generation OS with a virtualization feature is executed as a user program on a first virtual processor by selecting, in response to a cause of a call for a host VMM, one of a guest status area (221) for executing a user program on a second virtual processor and a host status area (222) for executing the guest VMM, and by updating a guest status area (131) of a shadow VMCS for controlling a physical processor. Accordingly, without a decrease in performance of a virtual computer, the next-generation OS incorporating the virtualization feature is executed on a virtual server, and the next-generation OS and an existing OS are integrated on a single physical computer.

A multiple-core processor with support for multiple virtual processors. In one embodiment, a processor may include a cache including a number of cache banks, a number of processor cores and core/bank mapping logic coupled to the cache banks and processor cores. During a first mode of processor operation, each of the processor cores may be configurable to access any of the cache banks, and during a second mode of processor operation, the core/bank mapping logic may be configured to implement a plurality of virtual processors within the processor. A first virtual processor may include a first subset of the processor cores and a first subset of the banks, and a second virtual processor may include a second subset of the processor cores and a second subset of the cache banks. Subsets of processor cores and cache banks included in the first and second virtual processors may be distinct.