Microsoft Technology Licensing, LLC

Forrest Curtis Foltz

Eric P Traut

Rene Antonio Vega

Bryan M Willman

Matthew Douglas Hendel

Adrian J Oney

Mukund Sankaranarayan

Dale Alan Sather

Michael B Jones

Jai Srinivasan

William G Parry

Jayachandran Raja

Terje Kristian Backman

Yimin Deng

Sean C McDowell

David S Bakin

Yue Zuo

George H Shaw

Andy R Raffman

David N Cutler

Benjamin W Slivka

Hoi Huu Vo

Suyash Sinha

Vivek Bhanu

Samer Arafeh

Robert M McKaughan

Robin C Speed

Vivek P Divakara

Hoyuen Chau

Kenneth D Ray

Scott Field

George M Moore

Brandon S Baker

John Charles Dunn

Andrew John Thornton

Rajasekhar Abburi

John Te-Jui Sheu

Ellsworth Davis Walker

Zhong Deng

Robin Speed

Wassef Haroun

Edward L Stubbs

Joy Ganguly

Ho Yuen Chau

Felix Gerard Andrew

Arie Van Der Hoeven

Scott A Field

Samer N Arafeh

In various embodiments, methods and systems, for implementing proxy objects are provided. A task request directed to a driver component is intercepted at a proxy object component. The task request is an Input/Output or a session task. A proxy object is generated for the task request at the proxy object component. The task request is communicated from the proxy object component to the driver component. A modification indication to modify the driver component is received. A standby mode is initiated at the proxy object component and the driver component, the standby mode comprises processing task requests and proxy objects based on standby operations. A determination that the driver component has been modified to a modified version of the driver component is made. A recovery mode is initiated at the proxy object component and the driver component, the recovery mode comprises processing task requests and proxy objects based on recovery operations.

Proxy object system

Efficient power management of a system with virtual machines is disclosed. In particular, such efficient power management may enable coordination of system-wide power changes with virtual machines. Additionally, such efficient power management may enable coherent power changes in a system with a virtual machine monitor. Furthermore, such efficient power management may enable dynamic control and communication of power state changes.

Efficient power management of a system with virtual machines

Computerized methods, systems, and computer-storage media for allowing virtual machines (VMs) residing on a common physical node to fairly share network bandwidth are provided. Restrictions on resource consumption are implemented to ameliorate stressing the network bandwidth or adversely affecting the quality of service (QoS) guaranteed to tenants of the physical node. The restrictions involves providing a scheduler that dynamically controls networking bandwidth allocated to each of the VMs as a function of QoS policies. These QoS policies are enforced by controlling a volume of traffic being sent from the VMs. Controlling traffic includes depositing tokens into token-bucket queues assigned to the VMs, respectively. The tokens are consumed as packets pass through the token-bucket queues. Upon consumption, packets are held until sufficient tokens are reloaded to the token-bucket queues.

Applying policies to schedule network bandwidth among virtual machines

Computerized methods, systems, and computer-storage media for throttling requests from virtual machines (VMs) to a hard-disk drive (HDD) are provided. When a request for disk I/O is received from a VM, a disk-drive model that simulates performance characteristics of the HDD is accessed. During access, the disk-drive model's estimation of HDD parameters and the disk-drive model's estimation of a current state of a disk head of the HDD are gathered. A projected execution time to carry out the request is computed as a function of the estimated HDD parameters and the estimated current state of the disk head. Also, an actual execution time to carry out the request is measured upon allowing the request to pass to the HDD. Using a comparison of the projected execution time and the actual execution time, the traffic of the requests from the VMs is throttled.

Throttle disk I/O using disk drive simulation model

Techniques for grouping individual processors into assignment entities are discussed. Statically grouping processors may permit threads to be assigned on a group basis. In this manner, the burden of scheduling threads for processing may be minimized, while the processor within the assignment entity may be selected based on the physical locality of the individual processors within the group. The groupings may permit a system to scale to meet the processing demands of various applications.

Kernel processor grouping

This document describes tools capable of making a portion of operating-system memory associated with a protection agent unalterable or inaccessible from an operating-system privilege mode. In some embodiments, these tools are capable of creating a protection-agent privilege mode by requesting that a virtual machine monitor protect this portion of operating-system memory. In other embodiments, these tools are capable of creating the protection-agent privilege mode by virtualizing a physical processor into multiple virtual processors, at least one of which is a protection-agent virtual processor designed to run the protection agent. By making this portion of operating-system memory unalterable or inaccessible from the operating-system privilege mode, the protection agent may be less vulnerable to attacks by entities operating within the operating-system privilege mode.

Protection agents and privilege modes

Page tables in the last level of a hierarchical page table system are scanned for candidate page tables. Candidate page tables are converted to large pages, having a page table entry in a level before the last level of the hierarchical page table system adjusted to be associated with the newly created large page. Upon receiving a notification that a large page is to be converted into a page table, a new page table is created. Each entry in the new page table is associated with a small segment of memory in the large page and an entry in a page table one level before the last level in a hierarchical page table system is adjusted to be associated with the new page table.

Opportunistic page largification

This document describes tools capable of enabling a protection agent to determine, from memory inaccessible from an operating-system privilege mode, whether one or more resources of an operating system have been modified. In some instances, these tools may enable the protection agent to reside within a virtual machine monitor. In other instances, the tools may enable the protection agent to reside within a distinct virtual partition provided by the virtual machine monitor. By operating outside of the operating-system privilege mode, the protection agent may be less vulnerable to attacks by entities operating within the operating-system privilege mode.

Protecting operating-system resources

Resource management architectures implemented in computer systems to manage resources are described. In one embodiment, a general architecture includes a resource manager and multiple resource providers that support one or more resource consumers such as a system component or application. Each provider is associated with a resource and acts as the manager for the resource when interfacing with the resource manager. The resource manager arbitrates access to the resources provided by the resource providers on behalf of the consumers, e.g., using a priority-based policy. A resource consumer creates an 'activity' at the resource manager and builds one or more 'configurations' that describe various sets of preferred resources required to perform the activity. Each resource consumer can specify one or more configurations, which may be ranked, for each activity. This allows the resource consumers to be dynamically changed from one configuration to another as operating conditions change.

Resource manager architecture

An operating system is described that is capable of ascertaining whether it is executing in a virtual machine environment and is further capable of modifying its behavior to operate more efficiently and provide optimal behavior in a virtual machine environment. An operating system is enlightened so that it is aware of VMMs or hypervisors, taking on behavior that is optimal to that environment. The VMM or hypervisor informs the operating system of the optimal behavior, and vice versa.

Efficient operating system operation on a hypervisor

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Woodinville, WA, United States of America

Forrest Curtis Foltz