Patent Publication Number: US-10768972-B2

Title: Managing virtual machine instances utilizing a virtual offload device

Description:
INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS 
     Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are incorporated by reference under 37 CFR 1.57 and made a part of this specification. 
     BACKGROUND 
     Generally described, computing devices utilize a communication network, or a series of communication networks, to exchange data. Companies and organizations operate computer networks that interconnect a number of computing devices to support operations or provide services to third parties. The computing systems can be located in a single geographic location or located in multiple, distinct geographic locations (e.g., interconnected via private or public communication networks). Specifically, data centers or data processing centers, herein generally referred to as a “data center,” may include a number of interconnected computing systems to provide computing resources to users of the data center. The data centers may be private data centers operated on behalf of an organization or public data centers operated on behalf, or for the benefit of, the general public. 
     To facilitate increased utilization of data center resources within the data centers, virtualization technologies may allow a single physical computing device to host one or more instances of virtual machines that appear and operate as independent computing devices to users of a data center. With virtualization, software applications running on the physical computing device can create, maintain, delete, or otherwise manage virtual machine instances in a dynamic manner. 
     Use of the data centers in increasing numbers has created increased demand for the computing resources. Even with virtualization technologies, the number of available resources that can be provided to the virtual machines is limited, at least in part, by the software applications managing the virtual machine instances in the physical computing devices. The cost associated with changing the existing hardware resources for better hardware components can be a considerable expense. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The foregoing aspects and many of the attendant advantages of this disclosure will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings. 
         FIG. 1  is a block diagram depicting a physical computing device with an offload device and a plurality of virtual machine instances. 
         FIG. 2A  illustrates an embodiment of a state flow diagram depicting the configuration of virtual machine instances on the physical computing device and virtual components on an offload device utilizing a control plane manager. 
         FIG. 2B  illustrates an embodiment of a state flow diagram depicting the configuration of virtual machine instances on the physical computing device and virtual components on an offload device by a virtual machine monitor. 
         FIG. 3A  illustrates an embodiment of a state flow diagram depicting indirect communication between a virtual machine instance and a virtual component via the virtual machine monitor. 
         FIG. 3B  illustrates an embodiment of a state flow diagram depicting direct communication between a virtual machine instance and a virtual component. 
         FIG. 4  illustrates a flow diagram of a routine for determining a configuration of a virtual environment on a physical computing device and an offload device by a control plane manager. 
         FIG. 5  illustrates a flow diagram of a routine for the configuration of a virtual environment on a physical computing device and an offload device. 
         FIG. 6  illustrates a flow diagram of a routine for indirect communication between the host computing device and the virtual device via the virtual machine monitor. 
         FIG. 7  is a block diagram depicting an embodiment of a physical computing device configured with a virtual offload device. 
         FIG. 8  is a block diagram depicting an embodiment of an environment including a plurality of physical computing configured to communicate with an offload device. 
     
    
    
     DETAILED DESCRIPTION 
     Generally described, a physical computing device can be configured to host a number of virtual machine instances. Specifically, such physical computing devices can execute a virtual machine monitor can be used to manage multiple aspects of virtual machine instances. Such a virtual machine monitor may often be referred to as a “hypervisor.” The virtual machine monitor can associate and manage three primary virtualized resources to instantiated virtual machine instances, namely, virtual processing resources, virtual memory resources, and virtual input/output (I/O) resources, collectively or individually referred to as virtual components. 
     Although referred to as virtual components, the instantiation and operation of the virtual components requires computing resources of the physical computing device to implement. Generally, the virtual machine monitor will manage virtual components for each instantiated virtual machine instance on the physical computing device. As a result, physical computing resources are consumed to support the instantiated virtual components of each instantiated virtual machine instance and reduce the availability of the physical computing device resources for instantiated virtual machine instances or additional virtual machine instances. 
     The present application relates to systems and methods for the managing the instantiation and execution of virtual machines instances using a physical computing device and an offload device. In accordance with an illustrative embodiment, the offload device corresponds to an independent computing device that includes physical computing resources (e.g., processor and memory) separate from the physical computing resources associated with the physical computing device hosting the instantiated virtual machine instances. The offload device can be connected to the physical computing device via an interconnect interface. The interconnect interface can be a high speed, high throughput, low latency interface such as a Peripheral Component Interconnect Express (PCIe) interface. The offload device can be used to control the virtual machine monitor and emulate certain virtual components associated with the instantiated virtual machine instances, thereby decreasing the need to utilize physical computing resources in the execution of the instantiated virtual machine instances. 
     In accordance with an illustrative embodiment, the offload device can be used to instantiate virtual machines on the physical computing device. For example, the offload device can receive a command from a control plane manager via a network interface integrated into the offload device or a management domain and instruct the virtual machine monitor to launch virtual machines. In addition, the virtual machine monitor can provide resource information regarding the physical computing to the control plane manager via the offload device. The control plane manager can determine based on the resource information, such as the specific hardware configuration, and other information, such as the anticipated use of the physical computing device, the configuration of virtual machine instances on the physical computing device and virtual components on the offload device. The control plane manager can provide instructions to the virtual machine monitor to instantiate virtual machine instances in the determined configuration and instruct the offload device to instantiate virtual components in the determined configuration. The virtual machine monitor can provide mapping of the instantiated virtual components on the offload device such that the virtual machine instances can recognize and communicate with the virtual components through the interface bus. 
     In accordance with another illustrative embodiment, the virtual machine monitor can be configured to instantiate virtual machine instances on the physical computing device and instantiate respective virtual components on the offload device. The configuration of the virtual machine instances can determine the virtual components that are instantiated on the offload device on behalf of the instantiated virtual machine instances. The virtual machine monitor can also provide mapping of the instantiated virtual components on the offload device such that the virtual machine instances can recognize and communicate with the virtual components through the interface bus. 
     In accordance with an illustrative embodiment, the instantiated virtual I/O components on the offload device are configured to execute or process at least a portion of the I/O requests generated by the instantiated virtual machine instances. Illustratively, the virtual machine instances can communicate one or more I/O requests with the instantiated virtual I/O components on the offload device. In some aspects, the instantiated virtual machine instances may communicate directly with the virtual I/O components via the interface bus. In other aspects, the instantiated virtual machine instances can communicate indirectly with the virtual I/O components via the virtual machine monitor. In this aspect, the virtual machine monitor can use a translation table to route the I/O request to the virtual component. The type of communication can be based, at least in part, on communication protocols associated with the virtual I/O components or other criteria. 
     While specific embodiments and example applications of the present disclosure will now be described with reference to the drawings, these embodiments and example applications are intended to illustrate, and not limit, the present disclosure. Specifically, while various embodiments and aspects of the present disclosure will be described with regard to illustrative components of host computing device, one or more aspects of the present disclosure can be applied with regard to different types or configurations of physical computing devices or combinations thereof. 
       FIG. 1  illustrates an embodiment of a physical computing device  100  configured to host virtual machine instances  120  and interact with an offload device  130 . The physical computing device  100  includes one or more processing units  102 , such as one or more CPUs. The physical computing device  100  includes memory  104 , which may correspond to any combination of volatile or non-volatile computer-readable storage media. The memory  104  may store information which includes various programs, program data, and other modules. The programs stored in the memory can include a virtual machine monitor application  110  that can manage the virtual machine instances (e.g., by allocating memory to each virtual machine instance and scheduling virtual processors to run on physical processors). The physical computing device  100  can correspond to a wide variety of devices, such as servers, that include a wide variety of software and hardware components and configurations. The physical computing device  100  can include a local data store (not shown), or be configured to communicate with a data store over a network (not shown). 
     The physical computing device  100  is capable of hosting a plurality of virtual machine instances  120 . The virtual machine monitor  110  can manage virtual machine instances  120  hosted on the physical computing device  100 . Illustratively, the management of the virtual machine instances  120  can include the instantiation of the virtual machine instance and the instantiation of virtual components utilized in the execution of the virtual machine instance. Additionally, as will be explained in greater detail, the management of the virtual instances can further include the management of interaction between the virtual machine instances and the offload device  130  In the illustrated embodiment, the physical computing device  100  includes two instantiated, or hosted, virtual machine instances  120 , virtual machine instance “A” and virtual machine instance “B”. One skilled in the relevant art will appreciate, however, that the physical computing device  100  can host any number of virtual machine instances and is not limited to the hosting of the two virtual machine instances illustrated in  FIG. 1 . 
     With continued reference to  FIG. 1 , the offload device  130  can be operably coupled to the physical computing device  100  via the interconnect interface  106 . The interconnect interface  106  can refer to a physical communication interface on the physical computing device  100 . The interconnect interface  106  can be an electrical communication interface, an optical communication interface or other type of interconnect interface known in the art. The interconnect interface  106  can be configured to provide communications between components hosted on the offload device  130  with the virtual machine instances  120  hosted on the physical computing device  100 . Illustratively, the configuration of the interconnect interface can be optimized based on specific criteria, such as low latency, high speed, and high bandwidth, among others. In some embodiments, the interconnect interface can correspond to a high speed serial computer expansion bus, such as a Peripheral Component Interconnect Express (PCIe) bus. However, one skilled in the relevant art will appreciate that the interconnect interface may incorporate alternative or additional standard interconnect interfaces well known to those skilled in the art of computer architectures. 
     In an example embodiment, the offload device  130  is a computing device, or partial computing device, operably coupled to the physical computing device  100 . In some embodiments, the offload device  130  is physically coupled to the physical computing device  100  as well. The offload device  100  includes one or more processing units  132 , such as one or more CPUs. The offload device  130  includes memory  134 , which may correspond to any combination of volatile or non-volatile computer-readable storage media. The memory  134  may store information which includes various programs, program data, and modules, such as a management module  138  and a device emulation module  139 . The management module  138  can management component can be configured to determine the type of virtual components to instantiate based on configuration information for the virtual machine instance. The device emulation module  139  can be configured to perform the emulation and instantiation of the virtual components on the offload device  130 . The processor  132  and memory  134  of the offload device  130  are separate from the processor  102  and memory  104  of the physical computing device  100 . The offload device  130  can include a local data store (not shown), and/or be configured to communicate with a data store over a network (not shown). 
     The offload device can include a network interface controller (NIC)  136 . The offload device can be in communication with a control plane manager  150  (illustrated in  FIG. 2A ) via a network. The offload device can be configured act as an intermediary for providing instructions from the control plane manager  150  to the virtual machine monitor  110 , which will be explained in greater detail below with respect to  FIG. 2A . 
     As will be explained in greater detail below, the offload device  130  can host and emulate one or more virtual components that are used by the instantiated virtual machine instances substantially independent of one or more physical computing device  100  resources. The offload device  130  can be dynamically reconfigurable, such that the virtual components  140  can be removed, changed, added, or otherwise reconfigured to address the configuration of the virtual machine instances  120  on the physical computing device  100 . Accordingly, the offload device  130  would use at least a portion of the physical computing resources on the offload device to carry out the function of the instantiated virtual components. By way of example, operations executed on the offload device  130  can be carried out using the computing resources (e.g., processor  132  and memory  134 ) without requiring the usage of the physical computing device&#39;s  100  computing resources (e.g., processor  102  and memory  104 ). 
     In accordance with an illustrative embodiment, at least some portion of the virtualized components hosted on the offload device  130  correspond to virtual I/O components configured to execute I/O functionality on behalf of instantiated virtual machine instances. As illustrated in  FIG. 1 , the offload device  130  can include virtual I/O component groups  142 . Each virtual I/O component groups  142  corresponds to a virtual machine instance  120  on the physical computing device  100 . In the illustrated embodiment the offload device  130  includes virtual I/O component group A is associated with virtual machine instance A and virtual I/O component group B associated with virtual machine instance B. Each virtual I/O component group includes a plurality of virtual components  140   
     Generally described, the virtual machine monitor  110  executed on the physical computing device  100  is configured to manage various aspects associated with instantiated virtual machines instances. In an embodiment, the management operations can be split between the virtual machine monitor and a management domain, such as a Domain-0, that runs on physical computing device  100 . In yet another embodiment, all or portions of the programs that run within Domain-0 can instead run on the offload device  130 . The virtual machine monitor  110  can be executed directly on the physical computing system hardware. The virtual machine monitor can function like a host operating system for the physical computing device  100 . The virtual machine monitor  110  can control the hardware of the physical computing device  100  and manage and configure virtual machine instances  120  running on the physical computing device  100 . The virtual machine monitor  110  can implement management functions that provide direct access to the hardware of the physical computing device  100 . 
     To support hosted virtual machine instances, the virtual machine monitor  110  can instantiate guest domains on the physical computing device  100  for each virtual machine instances  120  by allocating the guest domains memory and time on the physical CPUs. As previously described, the allocated virtual resources include three primary virtualized resources that are utilized by the instantiated virtual machine instances, namely, virtual processing resources, virtual memory resources, and virtual I/O resources. In some embodiments, the configuration of the virtual machine instances  120  can be determined by a control plane manager  150  as described in greater detail in  FIG. 2A . In some embodiments, the virtual machine monitor  110  can determine the configuration of the virtual machine instances as described in greater detail in  FIG. 2B . 
     Each virtual machine instance  120  is provisioned virtual resources that are implemented by the physical computing resources of the physical computing device  100 . For example, a virtual machine instance can be allocated a virtual processing resources  122  and virtual memory resources  124  that represent logically provisioned allocations of underlying computing resources of the physical computing device (e.g., processor  102  and memory  104 ). Some of the virtual resources, such as virtual I/O resources, can be offloaded to the offload device  130 . The configuration of the virtualized resources for each virtual machine instance  120  can vary. For example, virtual machine instance A and virtual machine instance B can have different allocations of virtualized computing resources. 
     The virtual machine instances  120  may be provisioned to provide a variety of different desired functionalities depending on the needs of a data center or client. Examples of the types of desired functionality can include, but are not limited to: database management, serving or distributing data or content (e.g., Web servers), managing load balancing or network resources, managing network connectivity or security, providing network addressing information, managing client or server redirection, or other functionalities. In some embodiments, the virtual machine instances  120  may be provisioned to implement portions of a hosted network or to simulate one or more components of a hosted network. Illustratively, the virtual machine instances  120  may be configured to provide specific functionality associated with the components of a hosted network or simulation of the components of the hosted network. The virtual machine instances  120  may be provisioned generically when a desired functionality is not specified or is otherwise not available. 
     As previously describe, aspects of the present application relate to the hosting of virtual I/O components on the offload device  130  in a manner that reduces the execution of I/O functionality by the hosted virtual resources on the physical computing device  100 . Each virtual machine instance  120  is associated with virtual components  140  grouped into virtual I/O component groups  142 . The virtual machine monitor  110  is responsible for the provisioning of virtual I/O component groups  142  for each of the virtual machine instances  120 . The virtual components  140  can be logically grouped based on their association with a virtual machine instance  120 . The virtual machine monitor  110  can assign memory address ranges to virtual components within the memory allocated to virtual machine instances. For example, in  FIG. 1 , virtual I/O component group A is associated with virtual machine A and the virtual I/O component group B is associated with virtual machine B. In some embodiments, the virtual components  140  can be provisioned and emulated using the computing resources (e.g., processor  132  and memory  134 ) of the offload device  130 . For example, the offload device  130  can run one or more programs that simulate the functions of hardware components that would be typically found on a motherboard of a computer system. 
     The virtual components  140  represent a set of virtual functions that can be implemented by a virtual machine instances  120 . The virtual components  140  can provide virtual I/O functions that emulate the I/O functions of hardware computing devices found in a physical computing device. For example, the virtual components can correspond to I/O device types such as the real time clock (RTC), storage controller, network interface controller (NIC), programmable interrupt controller (PIC), peripheral component interconnect (PCI) bus, disk controller, SCSI controller, floppy drive, keyboard and mouse ports, monitor ports, serial ports, keyboard controller, ISA bus, and other I/O devices. The virtual components  140  are sometimes referred to as virtual devices. In a virtual computing environment not every function needs to be virtualized for every machine. The virtual machine monitor  110  can determine which I/O devices need to be virtualized based on the configuration of the virtual machine instance  120 . 
     In addition to the functionality implemented by the virtual I/O components, the various virtual components  140  can be configured as to the specific communication protocols utilized by the instantiated virtual machines to access the I/O functionality. More specifically, in one embodiment, some of the virtual I/O components may correspond to a Port I/O communication protocol (“Port I/O virtual components”) and other virtual I/O components may correspond to a memory-managed I/O (MMIO) communication protocol (“MMIO virtual components”). 
     Port I/O virtual components can require specific communication protocols for communications between a virtual machine instance  120  and a Port I/O virtual component. In this embodiment, the virtual machine monitor  110  can function as an intermediary to handle the communication protocols required for the communication between the Port I/O virtual components and the virtual machine instance  120 . The virtual machine monitor  110  can include a translation table that is used for handling communication between the virtual machine instance and port I/O virtual components  140 , some MMIO components also use a translation table. The translation table can include a table for translating requests to and from the virtual machine instance  120  in order to route the requests to the correct addresses assigned to the virtual components  140 . Additional details regarding the communication between virtual machine instances  120  and virtual components  140  that utilize the virtual machine monitor  110  are described below in associated with  FIG. 3A . 
     The MMIO components can be configured such that the virtual machine instance  120  can communicate directly with the virtual component  140  by communicating with the memory addresses assigned to the virtual component  140 . Additional details regarding direct communication between virtual machine instances  120  and virtual components  140  described below in associated with  FIG. 3B . 
     The physical computing device  100  can be part of a network that includes multiple physical computing devices  100 . One skilled in the relevant art will appreciate that the network is logical in nature and can encompass physical computing devices  100  from various geographic regions. Additionally, the network can include one or more physical computing devices  100  that do not host virtual machine instances  120 . 
     The physical computing devices can be managed by a centralized management system, such as illustrated by the control plane manager  150  in  FIG. 2A . The control plane manager  150  can be configured to manage the operation and configuration of the physical computing devices  100  on the virtual network as well as select computer systems to host virtual machines and send launch instructions to the offload device  130  or a manager program that runs in Domain-0. The control plane manager  150  can determine configurations, operating parameters, resource allocations within virtual machine instances, for each physical computing device within a virtual network. In some embodiments, the managements system can comprise a plurality of control plane managers that control different allocations of physical computing devices. The control plane manager  150  can be in communication with the physical computing devices  100  through the offload device  130 . In some embodiments, the control plane managers can communicate directly with the offload device  130  and/or the physical computing devices  100 . 
       FIG. 2A  illustrates a block diagram depicting the configuration of virtual machine instances  120  on the physical computing device  100  and virtual components  140  on the offload device  130  by a control plane manager  150 . The control manager  150  can be in communication with the physical computing device  100  via the offload device  130 . The functions described in association with  FIG. 2A  can be performed in a different sequence, can be added, merged, or left out altogether (e.g., not all described acts or events are necessary for the practice of the algorithms). Moreover, in certain embodiments, functions, acts or events can be performed concurrently. For example, the operations associated with ( 6 ), ( 7 ) and ( 8 ) can occur in a different order or can occur concurrently. 
     At ( 1 ), the virtual machine monitor  110  can determine the available resources of the physical computing device. The available resources can include information such as the available computing resources, such as processor type, memory configuration, hardware component configuration, versioning information, and other information that identifies the resources of the physical computing device. The resource information can include current operating conditions, computer resource utilization information associated with the current configuration of the physical computing device  100 . In some embodiments, the resource information can include resource information associated with the offload device  130 . The resource information can be gathered based on a request provided by the offload device or the control plane manager. In some embodiments, the virtual machine monitor may be configured to provide the resource information based on a triggering condition, such as during a portion of the boot process. In some embodiments, the virtual machine monitor  110  can be configured to periodically transmit the resource information. 
     In some embodiments, the resource information associated with a physical computing device  100  can be stored in a data store configured for maintaining the resource information associated with each physical computing device. The data store can also store the current operational state of the physical computing device, such as the instances that are running on the physical computing device  100 . 
     At ( 2 ) the virtual machine monitor sends the resource information to the offload device. After receipt of the resource information, at ( 3 ) the offload device can send the resource information to the control plane manager. In some embodiments, the resource information provided by the virtual machine monitor  110  can be supplemented with resource information associated with the offload device  130 . In such instances, the resource information may be sent together with the virtual machine monitor resource information or sent separately. In some embodiments, the offload device  130  can periodically send information to the control plane manager  150  to provide an update regarding the status of instances that are operating on the physical computing device  100 . 
     At ( 4 ), the control plane manager can determine the configuration of the physical computing device  100  and the offload device  130 . The determination can be based, in part, on the received resource information and information independent of the resource information. For example, the control plane manager  150  can also base the configuration on other considerations, such as client specifications, the configurations of other physical computing devices  100 , such as clustered computing devices, or other considerations independent of the resource information associated with the physical computing device. In some instances the control plane manager can be configuring a new physical computing device  100 , updating an existing configuration a physical computing device  100 , adding/removing virtual instances, and/or performing other management function associated with the physical computing device  100 . 
     The control plane manager  150  can determine the configuration of the allocation of the virtual machine instances on the physical computing devices and virtual components on the offload devices. As part of the configuration of the physical computing device  100 , the control plane manager  150  can determine the virtualized hardware resources allocated to each virtual machine instance  120 . A virtual machine instance  120  can have a specific configuration according to the computing capacity of the virtual machine instance. This can be based on the resource information, requirements of a customer, the system, number of instances operating on a physical computing device  100 , and other considerations. 
     Based on the specific configuration of the virtual machine instances  120 , the control plane manager  150  can determine the virtual components  140  that are associated with a virtual machine instance. The virtual machine instances  120  may have different specifications associated with the software and/or hardware of the virtual machine instance  120 . The different specifications for the virtual machine instance  120  may require specific virtual components  140 , which may differ from the virtual components configured for other virtual machine instances  120 . 
     In some instances, the control plane manager  150  can receive a request to launch a new instance. Based on the request, the control plane manager  150  can filter out physical computing devices  100  that cannot host the instance, such as physical computing devices that are full, physical computing devices that do not have the necessary hardware, physical computing devices that are already hosting too many instances, or physical computing devices that do not meet the requirements for the new instance based on other reasons. The control plane manager can select a physical computing device from the remaining physical computing devices and sends a launch command to the offload device  130  or physical computing device with configuration instructions for launching the requested instance having a specific configuration. 
     At ( 5 ), configuration instructions are sent to the offload device  130  for configuration of the virtual components on the offload device  130 . In some embodiments, the configuration instructions for the virtual machine monitor are included with the offload device configuration instructions. In addition, in some embodiments the configuration instructions can be sent to the offload device  130  or a manager running in Domain( ) as part of an instance launch command. In this example, the control plan manager  150  may have selected the physical computing device  100  to host a virtual machine and sent a command to launch an instance to the physical computing device  100 . 
     At ( 6 ) the offload device can instantiate one or more virtual components  140  on the offload device  130  based on the configuration instructions received from the control plane manager. The virtual components  140  on the offload device  130  represent virtual IO functions that are provisioned for use by a virtual machine instance  120 . Some non-limiting examples of virtual components  140  that may be instantiated on an offload device  130  include, a network interface controller (NIC), a programmable interrupt controller (PIC), a keyboard controller, an ISA bus, a floppy drive, a keyboard port, a mouse port, a monitor port, and a serial port. Some of the virtual components  140  instantiated for the virtual machine instance  120  can be based on the configuration of the virtual machine instance  120 . Some of the virtual components  140  may be required for operation of the virtual machine instance  120 , regardless of whether the virtual component  140  will be used. Some of the virtual components  140  may be virtualizations of hardware components that exist on the offload device, whereas others may be emulations of hardware components that do not exist on the offload device. 
     At ( 7 ), configuration instructions are sent to the physical computing device from the offload device  130  for configuration of the virtual machine instances on the physical computing device  100 . In some embodiments, the configuration instructions for the virtual machine monitor  110  are sent directly from the control plane manager  150 . 
     At ( 8 ), the virtual machine monitor  110  can instantiate the virtual machine instances  120  based on the configuration instructions provided by the control plane manager  150  via the offload device  130 . In some embodiments, the control plane manager  150  can communicate directly with the virtual machine monitor  110 . The virtual machine monitor  110  provisions the logical virtualized resources that are associated with the underlying physical resources to each virtual machine instance, such as a VM processor  102  and VM memory  104  based on the configuration instructions. The virtual machine monitor  110  can also provision storage resources that are included locally on the physical computing device  100  or that are accessible via network. 
     In some embodiments, the virtual I/O components can be instantiated on the physical computing device  100  and the offload device  130 . In such embodiments, a portion of the virtual I/O components are instantiated on the physical computing device  100  and a portion of the virtual I/O components are instantiated on the offload device  130 . The division of the virtual I/O components between the physical computing device  100  and the offload device  130  can be determined by the configuration instructions. 
     In some embodiments, the virtual machine monitor can include a memory mapping unit that manages the mapping of virtual components  140  instantiated on the offload device  130  to the virtual machine instance  120 . The virtual machine monitor  110  can assign the virtual components  140  to memory addresses of the offload device. The addresses mapped to each virtual component  140  are provided to the virtual machine instance  120  associated with virtual component  140 . The virtual components  140  associated with same virtual machine instance  120  may not be sequentially arranged within the memory of the offload device. In some embodiments, the virtual machine monitor  110  can assign ranges of memory addresses on the offload device to each virtual machine instance  120 . For example, if there were 12 virtual machine instances  120  the virtual machine monitor  110  could assign separate ranges of memory addresses of the offload device  130  to each of the 12 virtual machine instances  120 . 
     In other embodiments, the hosted virtual components  140  can be configured to communicate directly with a virtual machine instance  120 . These virtual components  140  can be MMIO virtual components  140 . In this instance the offload devices exposes or otherwise provides access to the virtual components  140  directly to the virtual machine instance  120 . Some virtual components  140  can be configured to communicate indirectly with the virtual machine instance  120 . For indirect communication, the virtual machine instance  120  communicates with the virtual component via the virtual machine monitor  110 . The virtual machine monitor can create a translation table that is used to direct the IO communications between the virtual machine instance  120  and the offload device  130 . Different translation tables can be created for port I/O virtual components and MMIO virtual components. The processes for direct and indirect communication between the virtual machine instances  120  and the virtual components  140  are described in more detail with respect to  FIGS. 3A and 3B . 
       FIG. 2B  illustrates a block diagram depicting the configuration of virtual machine instances  120  on the physical computing device  100  and virtual components  140  on the offload device  130  by the virtual machine monitor  110 . The functions described in association with  FIG. 2A  can be performed in a different sequence, can be added, merged, or left out altogether (e.g., not all described acts or events are necessary for the practice of the algorithms). Moreover, in certain embodiments, functions, acts or events can be performed concurrently. 
     At ( 1 ), the virtual machine monitor  110  can configure the physical computing device  100  and the offload device  130 . The virtual machine monitor  110  runs on the hardware of the physical computing device  100  and can communicate with the offload device  130 . The virtual machine monitor  110  can configure guest domains for each of the virtual machine instances  120  on the physical computing device  100  and configure access to virtual components  140  on the offload device  130 . 
     The virtual machine monitor can configure any number of virtual machine instances  120 . The virtual machine instances  120  can be configured automatically based on defined criteria, instructions from other systems, or other types of instructions. The virtual machine monitor can also provide a management interface that can allow an administrator or other user to manually configure the virtual machine instances  120  on the physical computing device  100 . 
     With continued reference to  FIG. 2B , as part of the configuration of the physical computing device  100 , the virtual machine monitor  110  can determine the virtualized hardware resources allocated to each virtual machine instance  120 . A virtual machine instance  120  can have a specific configuration according to the computing capacity of the virtual machine instance. This can be based on the requirements of a customer, the system, number of instances operating on a physical computing device  100 , and other considerations. The configuration information can include configuring a translation table that is used for memory mapping to the I/O devices. 
     Based on the specific configuration of the virtual machine instances  120 , the virtual machine monitor  110  can determine the virtual components  140  that are associated with a virtual machine instance. The virtual machine instances  120  may have different specifications associated with the software and/or hardware of the virtual machine instance  120 . The different specifications for the virtual machine instance  120  may require specific virtual components  140 , which may differ from the virtual components configured for other virtual machine instances  120 . 
     After the configuration of a virtual machine instance  120  is determined, at ( 2 ), the virtual machine monitor  110  can instantiate the virtual machine instances  120 . The virtual machine instances  120  provide a domain for operating systems and applications to run. The virtual machine instances can be fully isolated from other virtual machine instances  120 . The virtual machine monitor  110  provisions the logical virtualized resources that are associated with the underlying physical resources to each virtual machine instance, such as a VM processor  102  and VM memory  104 . The virtual machine monitor  110  can also provision storage resources that are included locally on the physical computing device  100 , on the offload device  130 , or that are accessible via network. In combination with the provisioning of the virtual machine instances  120 , the virtual machine monitor is also responsible for provisioning the IO virtual components  140  that are required by the virtual machine instance. 
     In some embodiments, the virtual I/O components can be instantiated on the physical computing device  100  and the offload device  130 . In such embodiments, the virtual machine monitor  110  instantiates a portion of the virtual I/O components on the physical computing device  100  and a portion of the virtual I/O components on the offload device  130 . The division of the virtual I/O components between the physical computing device  100  and the offload device  130  can be determined by the configuration data associated with the virtual machine instance  120 . 
     At ( 3 ) the virtual machine monitor  110  or a Domain-0 can cause the offload device  130  to instantiate one or more virtual components  140  by sending information that identifies the type and umber of virtual components to instantiate. The virtual components  140  on the offload device  130  emulate functions performed by I/O physical components. Some non-limiting examples of virtual components  140  that may be instantiated on an offload device  130  include, a storage device, a network interface controller (NIC), a programmable interrupt controller (PIC), a keyboard controller, an ISA bus, a floppy drive, a keyboard port, a mouse port, a monitor port, and a serial port. Some of the virtual components  140  instantiated for the virtual machine instance  120  can be based on the configuration of the virtual machine instance  120 . Some of the virtual components  140  may be required for operation of the virtual machine instance  120 , regardless of whether the virtual component  140  will be used. Some of the virtual components  140  may be virtualizations of hardware components that exist on the offload device, whereas others may be virtualizations of hardware components that do not exist on the offload device. 
     In some embodiments, the virtual machine monitor can include a memory mapping unit that manages the mapping of virtual components  140  instantiated on the offload device  130  to the virtual machine instance  120 . The virtual machine monitor  110  can assign the virtual components  140  to memory addresses of the offload device. The addresses mapped to each virtual component  140  are provided to the virtual machine instance  120  associated with virtual component  140 . The virtual components  140  associated with same virtual machine instance  120  may not be sequentially arranged within the memory of the offload device. In some embodiments, the virtual machine monitor  110  can assign ranges of memory addresses on the offload device to each virtual machine instance  120 . For example, if there were 12 virtual machine instances  120  the virtual machine monitor  110  could assign separate ranges of memory addresses of the offload device  130  to each of the 12 virtual machine instances  120 . 
     In other embodiments, the hosted virtual components  140  can be configured to communicate directly with a virtual machine instance  120 . These virtual components  140  can be MMIO virtual components  140 . In this instance the offload devices exposes or otherwise provides access to the virtual components  140  directly to the virtual machine instance  120 . Some virtual components  140  can be configured to communicate indirectly with the virtual machine instance  120 . For indirect communication, the virtual machine instance  120  communicates with the virtual component via the virtual machine monitor  110 . The virtual machine monitor can create a translation table that is used to direct the IO communications between the virtual machine instance  120  and the offload device  130 . Different translation tables can be created for port I/O virtual components and MMIO virtual components. The processes for direct and indirect communication between the virtual machine instances  120  and the virtual components  140  are described in more detail with respect to  FIGS. 3A and 3B . 
       FIG. 3A  illustrates the components of the virtual network depicting communication between a virtual machine instance  120  and a virtual component  140  that uses the virtual machine monitor  110  as an intermediary between the virtual machine instance  120  and the virtual component. The diagram illustrates indirect communication between the virtual machine instance  120  and virtual component  140 . Indirect communication can occur when a virtual component  140  virtualizes a Port I/O device and some MMIO devices. The devices can require communication protocols that do not allow the virtual machine instance  120  to directly access the assigned memory addresses of the virtual components  140 . 
     At ( 1 ) an I/O request from the virtual machine instance  120  triggers a virtual machine exit, also referred to as a VM exit. A VM exit is in response to certain I/O requests and/or events that marks the point at which a transition is made between the virtual machine instance  120  currently running and the virtual machine monitor  110 , which must exercise system control to process the request. Virtual components  140  that use indirect communication, and thus trigger VM exits, are determined during initialization and instantiation of the virtual machine instance  120  and virtual components  140 . The I/O requests that can trigger the VM exit are Port I/O requests and some identified MMIO requests. The I/O request identifies a specific virtual function of a virtual component  140  and includes instructions for the identified virtual component  140 . When the VM exit is triggered by the I/O request, the virtual machine instance  120  sends the I/O request to the virtual machine monitor  110 . 
     At ( 2 ) the I/O request is received and translated by the virtual machine monitor  110 . The virtual machine monitor  110  receives the request and uses a translation table for translating the I/O request. The translation table can include entries for each virtual component  140  that requires a VM exit. The virtual machine monitor can include separate translation tables for different types of virtual components  140 . For example, Port I/O virtual components and MMIO virtual components can have different translation tables. In some embodiments, the translation table can combine the translation information for Port IO virtual components  140  and MMIO virtual components  140  into a single table. The configuration of the translation table can be preconfigured by the virtual machine monitor. The translation table can store the routing information used for routing the received I/O request to the identified virtual component  140 . After the I/O request is received, the virtual machine monitor can look up the I/O request in the translation table and route the request to the memory address of the offload device  130  that is responsive to the I/O request. 
     At ( 3 ), the I/O request is routed to the identified virtual component  140 B. The I/O request is sent from the physical computing device  100  over the interface to the offload device  130 . At ( 4 ) the I/O request is received and resolved by the virtual component  140 B. The virtual component  140 B can resolve the request based on the information contained in the I/O request. The virtual component  140  can resolve the request based on the virtual function that is assigned to the memory address identified in the I/O request. The processing of the request is performed by the computing resources of the offload device and does not utilize the computing resources assigned to the virtual machine instance  120 . The I/O request can be a simple read or write, or a complex algorithm that is implemented on the offload device. For example, the offload device  130  may execute one or more device emulator programs. The offload device  130  may process the request and identify the appropriate emulator based on characteristics of the request. Next, the device emulator can run and process the request. For virtual components  140  set up on the offload device, the type of request is not considered when determining whether route the request using the offload device. Rather, the virtual machine monitor  110  routes the request regardless of the operations that are to be performed based on the request. 
     Based on the type of the request, the resolution of the request performed by the virtual component  140  can differ. In some instances, the I/O request may require a response from the virtual component  140 B. In some instances, the I/O request is resolved and may send an acknowledgment back to the virtual machine instance. For example, a write command from the virtual machine instance  120  to the virtual device may require a response from the virtual component  140  to the virtual machine instance  120 . In which case, an acknowledgment can be sent from the virtual component  140  to the virtual machine instance  120 . 
     In some instances, the process continues when an I/O request requires a response from the virtual component  140  to the virtual machine instance, such as a read request. In which case, after the request is resolved the virtual component  140  responds to the request. At ( 5 ), the virtual component  140  sends a response to the I/O request. The response can include the information specific to the request and is dependent on the specific parameters of the I/O request and the virtual component, or may be an acknowledgement. 
     At ( 6 ), the virtual machine monitor  110  translates that response to the I/O request. The translation of the response is performed using the translation table to route the response to the virtual machine instance  120  that initiated the request. At ( 7 ), the response to the I/O request is sent to the identified virtual machine instance  120  from the virtual machine monitor based on the information stored in the translation table of virtual machine monitor. The response can be accompanied by a VM resume that closes out the VM exit. At this point, the process completes and can be reinitiated each time an IO request is required that uses the translation table of the virtual machine monitor to act as an intermediary between the virtual machine instance  120  and the virtual component. 
       FIG. 3B  illustrates a block diagram depicting direct communication between a virtual machine instance  120  and a virtual component. Virtual machine instances  120  can communicate directly with the MMIO virtual components. The MMIO virtual components  140  allow for direct communication between the virtual machine instance  120  and the memory registers assigned to the virtual component  140  without any interaction between the virtual machine instance  120  and the virtual machine monitor  110 . 
     At ( 1 ) the virtual machine transmits an I/O request to a virtual component. The virtual machine instance  120  transfers the request to the virtual component  140  using memory addressing assigned to the virtual component  140  during instantiation of the virtual machine instance  120  and the virtual component. The virtual component  140  can be assigned to a range of memory addresses for communication with the virtual machine instance. Depending on the type of request the virtual machine instance  120  can communicate with a specific memory register. The memory mapping of the virtual component  140  allows the virtual machine instance  120  to communicate directly with the virtual component  140  through the interconnect interface  106 . A memory management unit can translate device-visible virtual memory addresses to physical memory addresses on the offload device  130 . 
     At ( 2 ), the I/O request is resolved by the device. The I/O request can be any type of request such as a read or write request. The virtual component  140  can resolve the request based on the specific parameters of the request. The processing of the request is performed by the computing resources of the offload device and does not utilize the computing resources assigned to the virtual machine instance  120 . The I/O request can be a simple read or write, or a complex algorithm that is implemented on the offload device. For virtual components  140  set up on the offload device, the type of request is not considered when determining whether route the request using the offload device. Rather, the virtual machine monitor  110  routes the request regardless of the operations that are to be performed based on the request. 
     At ( 3 ), the virtual component  140  can generate a response and send it to the virtual machine instance. For example, an acknowledgment can be sent from the virtual component  140  to the virtual machine instance  120 . 
       FIG. 4  illustrates a flow diagram of a routine  400  depicting the configuration of a virtual environment on a physical computing device  100  and an offload device  130 . The steps of the routine  400  are being described as generally being performed by a control plane manager  150 . The functions described in association with  FIG. 4  can be performed in a different sequence, can be added, merged, or left out altogether (e.g., not all described acts or events are necessary for the practice of the algorithms). Moreover, in certain embodiments, functions, acts or events can be performed concurrently. 
     At block  402 , the control plane manager  150  receives resource information associated with the physical computing device and the offload device. The resource information can include information such as the available computing resources, such as processor type, memory configuration, hardware component configuration, versioning information, and other information that identifies the resources of the physical computing device and the offload device. The resource information can include current operating conditions, computer resource utilization information associated with the current configuration of the physical computing device  100  and the offload device. The resource information can be gathered based on a request provided by the offload device  130  or the control plane manager  150 . 
     As part of a request to launch a virtual machine, and as illustrated at block  404 , the control plane manager can determine a configuration for a virtual machine instance to launch on the physical computing device  100 . The determination can be based, in part, on the resource information and information independent of the resource information. For example, the control plane manager  150  can also base the configuration on other considerations, such as client specifications, the configurations of other physical computing devices  100 , such as clustered computing devices, or other considerations independent of the resource information associated with the physical computing device. 
     As part of determining the configuration of the virtual machine, the control plane manager  150  can determine the virtualized hardware resources that will need to be allocated to the virtual machine instance  120 . A virtual machine instance  120  can have a specific configuration according to the computing capacity of the virtual machine instance. This can be based on the resource information, requirements of a customer, the system, the number of instances operating on the physical computing device  100 , and other considerations. The virtual machine instances  120  may have different specifications associated with the software and/or hardware of the virtual machine instance  120 . The different specifications for the virtual machine instance  120  may require specific virtual components  140 , which may differ from the virtual components configured for other virtual machine instances  120 . 
     At block  406 , the configuration instructions are provided to the offload device  130  for configuration of the virtual components on the offload device  130 . The offload device can instantiate one or more virtual components  140  on the offload device  130  based on the configuration instructions received from the control plane manager. Based on the specific configuration of the virtual machine instances  120 , the offload device  130  and/or the virtual machine monitor can determine the virtual components  140  to instantiate on the offload device  130 . 
     At block  408 , configuration instructions are provided to the physical computing device from the offload device  130  for configuration of the virtual machine instances on the physical computing device  100 . In some embodiments, the configuration instructions for the virtual machine monitor  110  are sent directly from the control plane manager  150  to the virtual machine monitor. The virtual machine monitor  110  can instantiate the virtual machine instances  120  based on the configuration instructions provided by the control plane manager via the offload device. In some embodiments, functions associated with blocks  406  and  408  can occur substantially simultaneously in response to a instance launch request. 
       FIG. 5  illustrates a flow diagram of a routine  500  depicting the configuration of a virtual environment on a physical computing device  100  and an offload device  130 . The steps of the routine  500  are being described as generally being performed by a virtual machine monitor  110  on the physical computing device  100  and/or by management software on the offload device  130 , such as the management module  138  and device emulation module  139 . 
     At block  502  the virtual machine monitor  110  and management software running on offload device  130  boot on the physical computing device  100 . The virtual machine monitor  110  can instantiate instances on the physical computing device  100 . The virtual machine monitor  110  can control the provisioning of resources of the hardware resources from the machine to specific virtual machine instances  120  and those virtual machine instances  120  can then be logically associated with the underlying hardware resources. 
     After a request to launch an instance is received, and as illustrated at block  504 , the virtual machine monitor  110  can determine the configuration of the virtual machine instances  120 . The determination of the virtual machine instances  120  can be based on information provided from an administrator or control plane manager  150 . The configuration can be a default configuration based on defined operating procedures stored within the virtual machine monitor  110  or it can be passed to the offload device  130  from the control plane manager  150 . In some instances the virtual machine monitor may be manually controlled by a user in order to determine the configuration for the virtual machine instances  120 . The determination of the configuration of the virtual machine instances  120  can include the number of virtual machine instances  120 , the resources provisioned to each virtual machine instance, one or more machine image to use to generate each virtual machine instance, and other virtual machine instance  120  configuration information. The number of virtual machine instances  120  can be based on the computing resources of the physical computing device  100 , the offload device  130 , or other configuration parameter. The number of virtual machine instances  120  may not limited by any predefined limit. The provisioning of virtual computing resources assigned to each virtual machine instance  120  can be based on logical physical resources of the physical computing device  100 . The specific configuration of the virtualized computing resources can vary for each virtual machine instance. The virtualized computing resources can include a virtual machine CPU, virtual machine memory and other resources used for the operation of the virtual machine instance. The machine image used to instantiate a virtual machine instance can include the operating system (e.g., Windows®, Linux®, etc.), applications, and any other software. The type of virtual components  140  required by the virtual machine instance  120  can be based on the specific configuration of the virtual machine instance. The virtual machine monitor  110  can determine the allocation of virtual components  140  between the physical computing device  100  and the offload device  130 . The virtual machine instance  120  may be configured with some virtual components  140 , such as data stores, and the offload device  130  may be configured with some virtual components  140 . In some embodiments, the virtual components  140  may be allocated primarily to the offload device  130 . 
     At block  506 , the virtual machine monitor can instantiate the virtual machine instances  120  on the physical computing device  100 . Each virtual machine instance  120  is configured within a guest domain on the physical computing device  100 . Each guest domain is configured to be independent of the other guest domains. The instantiation of the virtual machine instance  120  includes the determined configuration of computing resources, software, and other components as determined at block  404 . In an example embodiment, the virtual machine monitor can determine the allocation of the virtual components  140  between the physical computing device  100  and the offload device  130 . For example, the virtual machine monitor may configure the physical computing device  100  to not have any virtual components  140  allocated to the physical computing device  100  and all of the virtual components  140  allocated to the offload device  130 . Alternatively, the management module  138  on the offload device  130  can determine the allocation of virtual components  140  between the physical computing device  100  and the offload device  130 . 
     At block  508 , the virtual components  140  can be configured on the offload device  130 . For example, either the virtual machine monitor, a domain-0 management program, or management programs on the offload device  130 , such as the management module  138  and the device emulation module  139 , can configure the virtual components  140 . The number and type of virtual components  140  on the offload device  130  can be based on the specific configuration of the virtual machine instance. The virtual components  140  can include MMIO virtual components  140  and Port IO virtual components  140 . The virtual components  140  on the offload device  130  can be logically partitioned according to their associated virtual machine instance  120 . The virtual components  140  are associated with virtual functions. The virtual components  140  are instantiated in the memory of the offload device  130 . In some instances the offload device  130  can have defined partitions that that include sequential ranges of memory assigned to a virtual machine instance. In some embodiments, the virtual components  140  on the offload device  130  are assigned to logical locations within the memory, which may not be sequential in nature. The instantiation of the virtual components  140  on the offload device  130  allows for the physical computing device  100  to not have to allocate memory to the instantiation of the virtual components  140 . Some of the virtual components  140  may never be using in a virtual operating environment but are required for the operation of the virtual machine instance. The instantiation of the virtual components  140  can result in resource usage overhead that reduces the available computing resources that are provisioned to the virtual machine instances  120 . By allocating the virtual components  140  on the offload device  130 , computing resources on the physical computing device  100  can be freed up for usage by the virtual machine instances  120 . 
     At block  510 , the virtual machine monitor can determine the memory mapping of the virtual components  140  and the communication between the virtual components  140  and the virtual machine instance. A memory manager unit can determine the memory mapping for enabling communication between the virtual machine instances and the virtual components  140 . Depending on the type of virtual component, the virtual machine monitor can allow for direct access to the virtual component  140  or can provide indirect access via the virtual machine monitor. For direct access the virtual machine monitor assigns addresses to the virtual components  140  that allow the virtual machine instance  120  to communicate directly with the virtual components. For indirect access, the virtual machine monitor  110  can configure a translation table for communication between the virtual machine instances  120  and the virtual components  140 . The translation table can include addressing information for port I/O virtual components  140  and some MMIO virtual components  140 . 
     The instantiation of the virtual components  140  on the offload device  130  can be done in parallel with the instantiation of the virtual machine instance  120  on the physical computing device  100 . Some steps can be done in parallel while others may be done sequentially. The steps are merely illustrative of logical processes that are being performed by the virtual machine monitor on the physical computing device  100  and the offload device  130 . 
       FIG. 6  is a flow diagram illustrating a routine  600  depicting indirect communication between the host computing device and the virtual device via the virtual machine monitor  110 . The steps of the routine  600  are being described as generally being performed by a virtual machine monitor  110  on the physical computing device  100 . 
     At block  602  the virtual machine monitor receives an I/O request from a virtual machine instance  120 , which is triggered by a VM exit. When the VM exit is triggered by the I/O request, the virtual machine instance  120  sends the I/O request to the virtual machine monitor. The I/O request comes from the virtual machine instance  120  for a specific virtual component. 
     At block  604 , the I/O request is translated by the virtual machine monitor  110 . The virtual machine monitor receives the request and has a translation table that is used for translating the I/O request. The translation table can include entries for each virtual component  140  that requires a VM exit. The virtual machine monitor can include separate translation tables for different types of I/O devices. For example, Port IO virtual components  140  and MMIO virtual components  140  can have different translation tables. In some embodiments, the translation table can combine the translation information for Port IO virtual components  140  and MMIO virtual components  140 . The configuration of the translation table can be preconfigured by the virtual machine monitor. The translation table can be a lookup table that can store the routing information for the virtual components  140 . When the I/O request is received, the virtual machine monitor can look up the I/O request in the translation table and determine the routing information for directing the I/O request to the correct location associated with the addressed virtual component on the offload device  130 . 
     At block  606 , the virtual machine monitor  110  routes the I/O request to the identified virtual component. The I/O request is sent from the physical computing device  100  over the interface bus to the offload device  130 . The processing of the request is performed by the computing resources of the offload device and does not utilize the computing resources assigned to the virtual machine instance  120 . The I/O request can be a simple read or write, or a complex algorithm that is implemented on the offload device. For virtual components  140  set up on the offload device, the type of request is not considered when determining whether route the request using the offload device. Rather, the virtual machine monitor  110  routes the request regardless of the operations that are to be performed based on the request. 
     At block  608 , the virtual machine monitor receives a response to the I/O request from the virtual component. When a response is not required, the virtual machine monitor  110  can receive an acknowledgment from the virtual component  140 . The response can include the information responsive to the request, which can be dependent on the specific parameters of the IO request and the virtual component. 
     At block  610 , the virtual machine monitor  110  translates that response to the I/O request. The translation of the response is performed using the translation table to route the response to the virtual machine instance  120  that initiated the request. 
     At block  612 , the response to the I/O request is sent to the identified virtual machine instance  120  from the virtual machine monitor based on the information stored in the translation table of virtual machine monitor. The response can be accompanied by a VM resume that closes out the VM exit. At this point the process completes and can be reinitiated each time an IO request is required that uses the translation table of the virtual machine monitor to act as an intermediary between the virtual machine instance  120  and the virtual component. 
       FIG. 7  illustrates another embodiment of a virtual operating environment for a physical computing device  100  with a virtual offload device  230 . The physical computing device  100  does not have a physical offload device like the embodiment illustrated in  FIG. 1 . In this embodiment of the virtual offload device  230 , the physical computing system hosts a plurality of virtual machine instances  120  and a virtual offload device  230 . The virtual offload device  230  is partitioned to a specific portion of the physical computing device  100 . The virtual offload device  230  is instantiated using the computing resources from the physical computing device  100  rather than from a separate offload device  130 . The virtual offload device  130  provides the same functionality as described in association with  FIGS. 1 through 5 . In this manner the virtual components  140  are logically partitioned to a single logical grouping which can consolidate the organization and optimization of the virtual components  140 . 
       FIG. 8  illustrates another embodiment of a virtual computing network comprising a plurality of physical computing devices  200 . The physical computing devices  200  are in communication with a physical offload device  130  via a interconnect interface  206 . In this embodiment, the physical computing device  100   s  are configured to share a common interconnect interface  206  that allows each of the physical computing device  100   s  to be in physical and electrical communication with the offload device  130 . The interconnect interface  206  provides each of the physical computing devices  200  with a high speed, high bandwidth, and low latency connection to the offload device  130 . 
     The offload device  130  can have a plurality of virtual offload devices  230  with each virtual offload device  230  associated with a specific physical computing device  200 . In this embodiment, there are three physical computing devices  200  and three virtual offload devices  230  on the hardware offload device  130 . The virtual offload devices  230  work in the same manner as the offload device  130  described in association with  FIGS. 1 through 5 . The offload device  130  can be partitioned between the three different devices and so there can be a partition of the device associated with each physical computing device  200 . 
     It is to be understood that not necessarily all objects or advantages may be achieved in accordance with any particular embodiment described herein. Thus, for example, those skilled in the art will recognize that certain embodiments may be configured to operate in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein. 
     All of the processes described herein may be embodied in, and fully automated via, software code modules executed by a computing system that includes one or more general purpose computers or processors. The code modules may be stored in any type of non-transitory computer-readable medium or other computer storage device. Some or all the methods may alternatively be embodied in specialized computer hardware. In addition, the components referred to herein may be implemented in hardware, software, firmware or a combination thereof. 
     Many other variations than those described herein will be apparent from this disclosure. For example, depending on the embodiment, certain acts, events, or functions of any of the algorithms described herein can be performed in a different sequence, can be added, merged, or left out altogether (e.g., not all described acts or events are necessary for the practice of the algorithms). Moreover, in certain embodiments, acts or events can be performed concurrently, e.g., through multi-threaded processing, interrupt processing, or multiple processors or processor cores or on other parallel architectures, rather than sequentially. In addition, different tasks or processes can be performed by different machines and/or computing systems that can function together. 
     The various illustrative logical blocks, modules, and algorithm elements described in connection with the embodiments disclosed herein can be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, and elements have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. The described functionality can be implemented in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the disclosure. 
     The various illustrative logical blocks and modules described in connection with the embodiments disclosed herein can be implemented or performed by a machine, such as a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor can be a microprocessor, but in the alternative, the processor can be a controller, microcontroller, or state machine, combinations of the same, or the like. A processor can include electrical circuitry configured to process computer-executable instructions. In another embodiment, a processor includes an FPGA or other programmable device that performs logic operations without processing computer-executable instructions. A processor can also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. Although described herein primarily with respect to digital technology, a processor may also include primarily analog components. For example, some or the entire signal processing algorithms described herein may be implemented in analog circuitry or mixed analog and digital circuitry. A computing environment can include any type of computer system, including, but not limited to, a computer system based on a microprocessor, a mainframe computer, a digital signal processor, a portable computing device, a device controller, or a computational engine within an appliance, to name a few. 
     The elements of a method, process, or algorithm described in connection with the embodiments disclosed herein can be embodied directly in hardware, in a software module stored in one or more memory devices and executed by one or more processors, or in a combination of the two. A software module can reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD ROM, or any other form of non-transitory computer-readable storage medium, media, or physical computer storage known in the art. An example storage medium can be coupled to the processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium can be integral to the processor. The storage medium can be volatile or nonvolatile. The processor and the storage medium can reside in an ASIC. The ASIC can reside in a user terminal. In the alternative, the processor and the storage medium can reside as discrete components in a user terminal. 
     Conditional language such as, among others, “can,” “could,” “might” or “may,” unless specifically stated otherwise, are otherwise understood within the context as used in general to convey that certain embodiments include, while other embodiments do not include, certain features, elements and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment. 
     Disjunctive language such as the phrase “at least one of X, Y, or Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to present that an item, term, etc., may be either X, Y, or Z, or any combination thereof (e.g., X, Y, and/or Z). Thus, such disjunctive language is not generally intended to, and should not, imply that certain embodiments require at least one of X, at least one of Y, or at least one of Z to each be present. 
     Any process descriptions, elements or blocks in the flow diagrams described herein and/or depicted in the attached figures should be understood as potentially representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or elements in the process. Alternate implementations are included within the scope of the embodiments described herein in which elements or functions may be deleted, executed out of order from that shown, or discussed, including substantially concurrently or in reverse order, depending on the functionality involved as would be understood by those skilled in the art. 
     It should be emphasized that many variations and modifications may be made to the above-described embodiments, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure and protected by the following claims.