BACKGROUND

[0001] In some examples, a virtual machine (VM) is an emulation of a computer system that provides the functionality of a physical computer system. A host machine may create and run multiple VM instances. In some examples, VMs may be "rented" and accessed from the cloud by users. When a user wants a VM to be provisioned, in some examples, the user may have many options to choose from and particular configurations to be made for the VM, such as operating system (OS), VM size, machine name, username, password, time zone, and/or the like.

SUMMARY OF THE DISCLOSURE

[0002] This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0003] Briefly stated, the disclosed technology is generally directed to virtual machines. In one example of the technology, categories of virtual machines are selected from a plurality of categories of virtual machines. In some examples, for each selected category of virtual machine, a cardinality of virtual machines of the selected category that are requested for provisioning is recorded over time. In some examples, for each selected category of virtual machine, a prediction algorithm is used to predict a cardinality of virtual machines for the selected category to be requested in the future, such that the prediction algorithm weighs under-prediction of the cardinality of virtual machines as costlier than over-prediction of the cardinality of virtual machines. In some examples, for the selected categories of virtual machines, an error for the predicted cardinalities of virtual machines for the selected categories is determined. In some examples, the prediction algorithm is updated over time based on the determined error. In some examples, an adjustment for the predicted cardinalities for virtual machines for the selected categories is performed. In some examples, for each selected category of virtual machine, a cardinality of virtual machines of the selected category of virtual machines are composed and booted with generic virtual machine artifacts such that the cardinality of virtual machines of the selected categories is the adjusted predicted cardinality of requested virtual machines for the selected category. In some examples, the booted virtual machines are caused to enter a state in which the booted virtual machines are polling for a configuration with user-specific compute settings and user-specific networking settings.

[0004] Other aspects of and applications for the disclosed technology will be appreciated upon reading and understanding the attached figures and description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Non-limiting and non-exhaustive examples of the present disclosure are described with reference to the following drawings. In the drawings, like reference numerals refer to like parts throughout the various figures unless otherwise

specified. These drawings are not necessarily drawn to scale.

[0006] For a better understanding of the present disclosure, reference will be made to the following Detailed Description, which is to be read in association with the accompanying drawings, in which:

[0007] FIG. 1 is a block diagram illustrating one example of a suitable environment in which aspects of the technology may be employed;

[0008] FIG. 2 is a block diagram illustrating one example of a suitable computing device according to aspects of the disclosed technology;

[0009] FIG. 3 is a block diagram illustrating an example of a system;

[0010] FIG. 4 shows a block diagram illustrating an example of the system of FIG.

3; and

[0011] FIGs. 5 A and 5B show a logical flow diagram illustrating an example of a process that may be employed by an example of the VM pool manager of FIG. 3 and/or 4, in accordance with aspects of the present disclosure.

DETAILED DESCRIPTION

[0012] The following description provides specific details for a thorough understanding of, and enabling description for, various examples of the technology. One skilled in the art will understand that the technology may be practiced without many of these details. In some instances, well-known structures and functions have not been shown or described in detail to avoid unnecessarily obscuring the description of examples of the technology. It is intended that the terminology used in this disclosure be interpreted in its broadest reasonable manner, even though it is being used in conjunction with a detailed description of certain examples of the technology. Although certain terms may be emphasized below, any terminology intended to be interpreted in any restricted manner will be overtly and specifically defined as such in this Detailed Description section.

Throughout the specification and claims, the following terms take at least the meanings explicitly associated herein, unless the context dictates otherwise. The meanings identified below do not necessarily limit the terms, but merely provide illustrative examples for the terms. For example, each of the terms "based on" and "based upon" is not exclusive, and is equivalent to the term "based, at least in part, on", and includes the option of being based on additional factors, some of which may not be described herein.

As another example, the term "via" is not exclusive, and is equivalent to the term "via, at least in part", and includes the option of being via additional factors, some of which may not be described herein. The meaning of "in" includes "in" and "on." The phrase "in one embodiment," or "in one example," as used herein does not necessarily refer to the same embodiment or example, although it may. Use of particular textual numeric designators does not imply the existence of lesser-valued numerical designators. For example, reciting "a widget selected from the group consisting of a third foo and a fourth bar" would not itself imply that there are at least three foo, nor that there are at least four bar, elements. References in the singular are made merely for clarity of reading and include plural references unless plural references are specifically excluded. The term "or" is an inclusive "or" operator unless specifically indicated otherwise. For example, the phrases "A or B" means "A, B, or A and B." As used herein, the terms "component" and "system" are intended to encompass hardware, software, or various combinations of hardware and software. Accordingly, for example, a system or component may be a process, a process executing on a computing device, the computing device, or a portion thereof.

Introduction

[0013] Briefly stated, the disclosed technology is generally directed to virtual machines. In one example of the technology, categories of virtual machines are selected from a plurality of categories of virtual machines. In some examples, for each selected category of virtual machine, a cardinality of virtual machines of the selected category that are requested for provisioning is recorded over time. In some examples, for each selected category of virtual machine, a prediction algorithm is used to predict a cardinality of virtual machines for the selected category to be requested in the future, such that the prediction algorithm weighs under-prediction of the cardinality of virtual machines as costlier than over-prediction of the cardinality of virtual machines. In some examples, for the selected categories of virtual machines, an error for the predicted cardinalities of virtual machines for the selected categories is determined. In some examples, the prediction algorithm is updated over time based on the determined error. In some examples, an adjustment for the predicted cardinalities for virtual machines for the selected categories is performed. In some examples, for each selected category of virtual machine, a cardinality of virtual machines of the selected category of virtual machines are composed and booted with generic virtual machine artifacts such that the cardinality of virtual machines of the selected categories is the adjusted predicted cardinality of requested virtual machines for the selected category. In some examples, the booted virtual machines are caused to enter a state in which the booted virtual machines are polling for a configuration with user-specific compute settings and user-specific networking settings.

[0014]In order to provide fully provisioned and fully configured virtual machines (VMs) to customers more quickly upon request, a pool of partially provisioned VMs may be maintained. The partially provisioned VMs may be configured except with respect to user-specific settings. When a customer requests a VM, a partially provisioned VM from the pool may be converted to a fully configured VM, fully configured with user-specific settings, without rebooting the partially provisioned VM, and therefore provided to a customer more quickly than if a VM were created and booted from scratch.

[0015]In some examples, some properties cannot be configured without reboot of a VM or recreating the VM, such as VM size, OS type, storage type, and/or the like. The VM pool manager may keep a suitable number of each combination of partially configured VMs that may be needed, of at least some of the possible categories of VM that may be requested by a customer.

[0016] A prediction algorithm, using an autoregressive integrated moving average (ARIMA) model, an artificial network network (ANN) system, any suitable prediction method, or any suitable combination thereof, may be used to predict the number of VMs in each of the selected categories of VMs. For each selected category, the number of VMs of that category that are requested may be recorded over time, and this data may be used to train the prediction algorithm.

[0017] The prediction algorithm may be updated over time for each category of VMs based on the error between the prediction and the actual number of VMs requested for the category. The prediction algorithm may weigh under-estimation of the number of requested VMs as costlier than the over-estimation of under-estimation of number of requested VMs. An adjustment may be made to the estimation of the prediction of the algorithm, such as using a minimum number of VMs and/or a maximum number of VMs for the category, adjusting for system constraints, and/or the like.

[0018] After the adjustment, VMs may be partially provisioned in each of the selected categories of VM, with the predictions used to determine how many VMs to partially provision in each of the selected categories. [0019] A partially configured VM may be provided by creating and booting a VM that is configured except with respect to certain user-specific settings. A bare minimum configuration may be used. Some configuration may be skipped during the bare minimum configuration, and some configurations may simply be "placeholders" that will be replaced when the VM is fully configured. For example, the partially configured VM may be configured with a placeholder machine name that will be replaced with a customer- specified machine name upon full configuration, and may be configured with a placeholder virtual network that will be replaced with a customer-specified virtual network upon full configuration.

[0020] In some examples, after completing the bare minimum configuration with certain configurations being placeholder values, the VM is caused to enter a state in which the VM is actively polling for a new, full configuration with user-specific settings. In some examples, the VM remains in this state until such a full configuration is published. When the full configuration is published, the VM may be caused to transition from a partially configured VM to a fully configured VM that is fully configured with user- specific settings, without rebooting the VM.

Illustrative Devices/Operating Environments

[0021] FIG. 1 is a diagram of environment 100 in which aspects of the technology may be practiced. As shown, environment 100 includes computing devices 110, as well as network nodes 120, connected via network 130. Even though particular components of environment 100 are shown in FIG. 1, in other examples, environment 100 can also include additional and/or different components. For example, in certain examples, the environment 100 can also include network storage devices, maintenance managers, and/or other suitable components (not shown).

[0022] As shown in FIG. 1, network 130 can include one or more network nodes 120 that interconnect multiple computing devices 110, and connect computing devices 110 to external network 140, e.g., the Internet or an intranet. For example, network nodes 120 may include switches, routers, hubs, network controllers, or other network elements. In certain examples, computing devices 110 can be organized into racks, action zones, groups, sets, or other suitable divisions. For example, in the illustrated example, computing devices 110 are grouped into three host sets identified individually as first, second, and third host sets 1 l2a-l l2c. In the illustrated example, each of host sets 1 l2a- 112c is operatively coupled to a corresponding network node l20a-l20c, respectively, which are commonly referred to as "top-of-rack" or "TOR" network nodes. TOR network nodes 120a- 120c can then be operatively coupled to additional network nodes 120 to form a computer network in a hierarchical, flat, mesh, or other suitable types of topology that allows communication between computing devices 110 and external network 140. In other examples, multiple host sets 1 l2a-l l2c may share a single network node 120.

Computing devices 110 may be virtually any type of general- or specific-purpose computing device. For example, these computing devices may be user devices such as desktop computers, laptop computers, tablet computers, display devices, cameras, printers, or smartphones. However, in a data center environment, these computing devices may be server devices such as application server computers, virtual computing host computers, or file server computers. Moreover, computing devices 110 may be individually configured to provide computing, storage, and/or other suitable computing services.

Illustrative Computing Device

[0023] FIG. 2 is a diagram illustrating one example of computing device 200 in which aspects of the technology may be practiced. Computing device 200 may be virtually any type of general- or specific-purpose computing device. For example, computing device 200 may be a user device such as a desktop computer, a laptop computer, a tablet computer, a display device, a camera, a printer, or a smartphone.

Likewise, computing device 200 may also be server device such as an application server computer, a virtual computing host computer, or a file server computer, e.g., computing device 200 may be an example of computing device 110 or network node 120 of FIG.

1. Likewise, computer device 200 may be an example any of the devices illustrated in FIG. 5, as discussed in greater detail below. As illustrated in FIG. 2, computing device 200 includes processing circuit 210, operating memory 220, memory controller 230, data storage memory 250, input interface 260, output interface 270, and network adapter 280. Each of these afore-listed components of computing device 200 includes at least one hardware element.

[0024] Computing device 200 includes at least one processing circuit 210 configured to execute instructions, such as instructions for implementing the herein-described workloads, processes, or technology. Processing circuit 210 may include a

microprocessor, a microcontroller, a graphics processor, a coprocessor, a field

programmable gate array, a programmable logic device, a signal processor, or any other circuit suitable for processing data. The aforementioned instructions, along with other data (e.g., datasets, metadata, operating system instructions, etc.), may be stored in operating memory 220 during run-time of computing device 200. Operating memory 220 may also include any of a variety of data storage devices/components, such as volatile memories, semi-volatile memories, random access memories, static memories, caches, buffers, or other media used to store run-time information. In one example, operating memory 220 does not retain information when computing device 200 is powered off. Rather, computing device 200 may be configured to transfer instructions from a non volatile data storage component (e.g., data storage component 250) to operating memory 220 as part of a booting or other loading process.

[0025] Operating memory 220 may include 4 ^th generation double data rate (DDR4) memory, 3 ^rd generation double data rate (DDR3) memory, other dynamic random access memory (DRAM), High Bandwidth Memory (HBM), Hybrid Memory Cube memory, HD- stacked memory, static random access memory (SRAM), or other memory, and such memory may comprise one or more memory circuits integrated onto a DIMM, SIMM, SODIMM, or other packaging. Such operating memory modules or devices may be organized according to channels, ranks, and banks. For example, operating memory devices may be coupled to processing circuit 210 via memory controller 230 in channels. One example of computing device 200 may include one or two DIMMs per channel, with one or two ranks per channel. Operating memory within a rank may operate with a shared clock, and shared address and command bus. Also, an operating memory device may be organized into several banks where a bank can be thought of as an array addressed by row and column. Based on such an organization of operating memory, physical addresses within the operating memory may be referred to by a tuple of channel, rank, bank, row, and column.

[0026] Despite the above-discussion, operating memory 220 specifically does not include or encompass communications media, any communications medium, or any signals per se.

[0027] Memory controller 230 is configured to interface processing circuit 210 to operating memory 220. For example, memory controller 230 may be configured to interface commands, addresses, and data between operating memory 220 and processing circuit 210. Memory controller 230 may also be configured to abstract or otherwise manage certain aspects of memory management from or for processing circuit 210.

Although memory controller 230 is illustrated as single memory controller separate from processing circuit 210, in other examples, multiple memory controllers may be employed, memory controller(s) may be integrated with operating memory 220, or the like. Further, memory controller(s) may be integrated into processing circuit 210. These and other variations are possible.

[0028] In computing device 200, data storage memory 250, input interface 260, output interface 270, and network adapter 280 are interfaced to processing circuit 210 by bus 240. Although, FIG. 2 illustrates bus 240 as a single passive bus, other configurations, such as a collection of buses, a collection of point to point links, an input/output controller, a bridge, other interface circuitry, or any collection thereof may also be suitably employed for interfacing data storage memory 250, input interface 260, output interface 270, or network adapter 280 to processing circuit 210.

[0029] In computing device 200, data storage memory 250 is employed for long term non-volatile data storage. Data storage memory 250 may include any of a variety of non-volatile data storage devices/components, such as non-volatile memories, disks, disk drives, hard drives, solid-state drives, or any other media that can be used for the non volatile storage of information. However, data storage memory 250 specifically does not include or encompass communications media, any communications medium, or any signals per se. In contrast to operating memory 220, data storage memory 250 is employed by computing device 200 for non-volatile long-term data storage, instead of for run-time data storage.

[0030] Also, computing device 200 may include or be coupled to any type of processor-readable media such as processor-readable storage media (e.g., operating memory 220 and data storage memory 250) and communication media (e.g.,

communication signals and radio waves). While the term processor-readable storage media includes operating memory 220 and data storage memory 250, the term "processor- readable storage medium," throughout the specification and the claims whether used in the singular or the plural, is defined herein so that the term "processor-readable storage medium" specifically excludes and does not encompass communications media, any communications medium, or any signals per se. However, the term "processor-readable storage medium" does encompass processor cache, Random Access Memory (RAM), register memory, and/or the like.

[0031] Computing device 200 also includes input interface 260, which may be configured to enable computing device 200 to receive input from users or from other devices. In addition, computing device 200 includes output interface 270, which may be configured to provide output from computing device 200. In one example, output interface 270 includes a frame buffer, graphics processor, graphics processor or accelerator, and is configured to render displays for presentation on a separate visual display device (such as a monitor, projector, virtual computing client computer, etc.). In another example, output interface 270 includes a visual display device and is configured to render and present displays for viewing.

[0032] In the illustrated example, computing device 200 is configured to communicate with other computing devices or entities via network adapter 280. Network adapter 280 may include a wired network adapter, e.g., an Ethernet adapter, a Token Ring adapter, or a Digital Subscriber Line (DSL) adapter. Network adapter 280 may also include a wireless network adapter, for example, a Wi-Fi adapter, a Bluetooth adapter, a ZigBee adapter, a Long-Term Evolution (LTE) adapter, or a 5G adapter.

[0033] Although computing device 200 is illustrated with certain components configured in a particular arrangement, these components and arrangement are merely one example of a computing device in which the technology may be employed. In other examples, data storage memory 250, input interface 260, output interface 270, or network adapter 280 may be directly coupled to processing circuit 210, or be coupled to processing circuit 210 via an input/output controller, a bridge, or other interface circuitry. Other variations of the technology are possible.

[0034] Some examples of computing device 200 include at least one storage memory (e.g. data storage memory 250), at least one operating memory (e.g., operating memory 220) and at least one processor (e.g., processing unit 210) that are respectively adapted to store and execute processor-executable code that, in response to execution, enables computing device 200 to perform actions, such as, in some examples, the actions of process 490 of FIG. 4, as discussed in greater detail below.

[0035] FIG. 3 is a block diagram illustrating an example of a system (300). System 300 may include network 330, as well as resource manager 341, VM pool manager 342, compute manager 343, storage manager 344, networking manager 345, and virtual machine host 351, which all may connect to network 330.

[0036] Resource manger 341 may be configured to communicate with customers, including receiving customer requests, and to coordinate actions based on customer requests. Resource manager 341 may also be configured to coordinate other high-level functions associated with VM management. In some examples, compute manager 343 manages the compute aspects of VMs, storage manager 344 manages the storage aspect of VMs, and networking manager 345 manages the networking aspect of VMs. In some examples, compute manager 343 also orchestrates management of other resources, including networking resources and storage resources, not just compute resources. In some examples, virtual machine host 351 is configured to create and run VMs, responsive to control from, inter alia, compute manager 343.

[0037] In some examples, VM pool manager 342 is configured to manage a pool of partially provisioned VMs. VM pool manager 342 may predict, for at least some categories of VMs, how many VMs of the category will be requested, and keep, in the pool, for each category of VM, the predicted number of partially provisioned VMs. The partially provisioned VMs may be booted and configured except with respect to customer- specific settings. In some examples, some properties cannot be configured without reboot of a VM or recreating the VM, such as VM size, OS type, storage type, and/or the like. VM pool manager 342 may manage keeping a suitable number of each combination of partially configured VMs that may be needed.

[0038] Network 330 may include one or more computer networks, including wired and/or wireless networks, where each network may be, for example, a wireless network, local area network (LAN), a wide-area network (WAN), and/or a global network such as the Internet. On an interconnected set of LANs, including those based on differing architectures and protocols, a router acts as a link between LANs, enabling messages to be sent from one to another. Also, communication links within LANs typically include twisted wire pair or coaxial cable, while communication links between networks may utilize analog telephone lines, full or fractional dedicated digital lines including Tl, T2, T3, and T4, Integrated Services Digital Networks (ISDNs), Digital Subscriber

Lines (DSLs), wireless links including satellite links, or other communications links known to those skilled in the art. Furthermore, remote computers and other related electronic devices could be remotely connected to either LANs or WANs via a modem and temporary telephone link. Network 330 may include various other networks such as one or more networks using local network protocols such as 6L0WPAN, ZigBee, or the like. In essence, network 330 includes any communication technology by which information may travel between resource manager 341, VM pool manager 342, compute manager 343, storage manager 344, and virtual machine host 351. Although each device or service is shown connected as connected to network 330, that does not mean that each device communicates with each other device shown. In some examples, some devices/services shown only communicate with some other devices/services shown via one or more intermediary devices. Also, although network 330 is illustrated as one network, in some examples, network 330 may instead include multiple networks that may or may not be connected with each other, with some of the devices shown communicating with each other through one network of the multiple networks and other of the devices shown communicating with each other with a different network of the multiple networks.

[0039] FIG. 4 is a block diagram illustrating an example of a system (400), which may be employed as an example of system 300 of FIG. 3. System 400 may include resource manager 441, VM pool manager 442, compute manager 443, storage manager 444, networking manager 445, and virtual machine host 451. Although only one virtual machine host is shown in FIG. 4, some examples of system 400 may include a large number of virtual machine hosts.

[0040] In various some virtualization environments, a VM (such as a Windows, Linux, or Unix VM) is created from scratch following a customer request for that VM.

For example, such creation may include retrieving an image from Platform Image Repository (PIR), copying the image to the customer's account, creating a VM with that image, and booting the VM up. Using a Windows VM as an example as follows, once started, the VM goes through Windows setup (specialized and out-of-box experience (OOBE) passes), which provisions the VM from the generalized image to a specialized image. Despite speed increases in modem computing systems, various amounts of time may be associated with creating a VM. For example, some VMs are associated with end- to-end "spin-up" times in the vicinity of one to five minutes, for example, depending on various factors such as operating system, network speed, resources of the physical hardware, virtualization system load, etc. The present disclosure may be employed, for example, by various providers and tenants of virtualization services to reduce "spin-up time" for VMs following customer requests for VMs. For example, various aspects of the present technology may be employed to facilitate at least partial configuration, provisioning, booting, or other steps typically performed prior to a VM being ready for customer use before a customer has requested the VM. By, for example, performing such steps prior to the request, the duration of time between the customer request and availably of the VM may be reduced in comparison to the typical amount of time associated with "spinning-up" a VM "from scratch" following a request.

[0041] Some examples of system 400 may operate in a hierarchy of multiple levels, with, for example, individual virtual machine hosts on the node level, in which there are clusters of virtual machines hosts, and regional data centers each consisting of multiple clusters. In other examples, other suitable arrangements may be employed. In some examples, one or more of compute manager 443, storage manager 444, and networking manager 445 each encompass devices operating at more than one level of the hierarchy. [0042] In some examples, VM pool manager 442 is configured to manage a pool of partially provisioned VMs. VMs may be booted and configured except with respect to customer-specific settings. In some examples, some properties cannot be configured without reboot of a VM or recreating the VM, such as VM size, OS type, storage type (e.g., premium storage or standard storage), type of internet routing (e.g., IPv4 or IPv6), processor resources, memory resources, and/or the like. VM pool manager 442 may manage keeping a suitable number of each combination of partially configured VMs that may be needed.

[0043] In some examples, each such type is a virtual machine combination type based on a combination of each parameter that is a property that cannot be configured without reboot but that is selectable by customer as an option.

[0044] VM pool manager 442 may determine how many partially provisioned VMs of each type/category are needed based on a predictive algorithm, such as an AREVIA model, an ANN system, any suitable prediction method, or any suitable combination thereof. For instance, the predictive algorithm may use the ARIMA model, an ANN system, both an ARIMA model and an ANN system with the results averaged or otherwise both taken into account to generate a final prediction, or the like. Other machine learning algorithms such as a Hidden Markov Model (HMM), and/or other suitable methods, may also be used. VM pool manager 442 does not necessarily cause the creation pre provisioned VMs and perform prediction for every possible category of VM. Rather, in some examples, some categories of VMs are selected for pre-provisioning, based on one or more suitable criteria such as popularity, profitability, or any other suitable criteria or combination thereof.

[0045] In some examples, for each selected category, the number of VMs of that category that are requested is recorded/stored over time in a database, and this data may be used to train the prediction algorithm. In some examples, for each of the categories of VMs to be predicted, the last N days (e.g., 14 days) are used to predict VMs needed for the next 24 hours. However, other suitable time periods may be employed, for both input data and for the amount of time predicted based on the input for each prediction. In some examples, data filtering and other functions may be performed before providing the data to the predictive algorithm. The error between the prediction and the actual number of VMs requested for the category may be determined/calculated. The prediction algorithm may be updated/refined over time for each category of VMs based on the error between the prediction and the actual number of VMs requested for the category. [0046] The prediction algorithm may weigh under-estimation of the number of requested VMs as costlier than the over-estimation of the number of requested VMs. An over-estimation of requested VMs of a category may result in increased costs, whereas an under-estimation may result in significantly increased spin-up times for customers. The increased cost of over-estimation may be mitigated by using preemptable VMs. If a category of VM is requested that is not currently partially provisioned, then a partially provisioned VM can be modified into the type of VM requested. In some examples, because the cost of over-estimation is relatively low, and because it is desirable to avoid customer frustration with excessive spin-up times, the predictive algorithm may accordingly weigh under-estimation as costlier than over-estimation.

[0047] VM usage may have cyclic usage patterns. For example, there may tend to be more VM usage earlier in the week than later in the week. There may also tend to be more VM usage during than day than during the night. There may also be an overall trend, such as VM usage increasing over time, such as by about 6-12% each month. By using at least two weeks of input data, both the trend and the cyclic usage patterns may be taken into account by the prediction algorithm. Different categories may have different cyclic usage patterns. For example, while some VM categories may have less usage on the weekend than during the weekend, and less usage at night then during the day, a VM category used primarily for gaming may instead tend to have more usage during the weekend than during the week, and may tend to have more usage at night than during the day.

[0048] An adjustment may be made to the estimation of the prediction of the algorithm, such as using a minimum number of VMs and/or a maximum number of VMs for the category, adjusting for system constraints, and/or the like. For instance, it may be desirable to ensure that a minimum number of VMs are available in each selected category of VMs, so there are always some VMs available for customers no matter how low the prediction is. As another example, it may be desirable for there to be a maximum number of VMs for safety reasons, and/or the like.

[0049] Also, the prediction algorithm itself does not necessarily take system constraints into consideration. There may be a limit to the number of VMs that can be provisioned. Even if the number of VMs of one particular category is less than the total number of VMs that can be provisioned, there may be a capacity limit on the total number of VMs that can be provisioned, and provisioning too many VMs in one category may prevent enough VMs from being provisioned in another category, for example. These system constraints and others may be taken into account in the adjustment to the predicted number of VMs for the category that are made before actually partially provisioning the VMs based on the predicted number.

[0050] Adjustments may also by made based on external considerations. For example, less usage may be expected on a holiday, which may be not be predicted by the prediction algorithm itself. Also, a particular announcement may be expected to result in increased usage of certain categories of VMs. For some prediction algorithms, elements of the prediction algorithm itself may be adjusted. For instance, if the ARJMA model is being used as the prediction algorithm, particular parameters such as equation coefficients or the like may be adjusted to account for external considerations. For an ANN system, it may not be possible to adjust for external considerations in the prediction itself. In some examples, an adjustment may be made as part of the adjustments made after the prediction to reflect the expected change in the number of requested VMs for each category based on the external considerations.

[0051] After the adjustment, VMs may be partially provisioned in each of the selected categories of VM, with the predictions used to determine how many VMs to partially provision in each of the selected categories. In some examples, predictions for each category of VMs may each be performed separately for each region. In other examples, other suitable scopes for the VMs to be partially provisioned may be employed.

[0052] VM pool manager 442 may determine how many partially provisioned VMs of each type are needed in the manner discussed above, and may then communicate to compute manager 443 in order to create each needed partially provisioned VM. When compute manager 443 receives a request from VM pool manager 442 to create a partially provisioned VM, in some examples, compute manager 443 then manages creation of the requested partially provisioned VM.

[0053] Partially provisioned VMs that are configured except with regard to certain user-specific settings may each be generated as follows. Without customer data, generic virtual machine artifacts are created. The generic artifacts may include at least one generic compute artifact, at least one generic network artifact, and possibly at least one generic storage artifact. The generic compute artifacts may include, for example, a placeholder machine name, a placeholder account username, a placeholder account password, and/or the like. The generic networking artifacts may include, for example, a placeholder virtual network, and a placeholder customer IP address. A VM is created/composed using the generic artifacts, using the particular combination of properties that are not reconfigured (e.g., VM size, OS type, storage type, processor resources, memory resources, etc.), and the VM is booted.

[0054] In some examples, pool manager 442 manages the VM pool. Pool manager 442 may be configured to determine which VMs should be created for the pool. Pool manager 442 may communicate with compute manager 443 in order for the VMs to be created, with the creation of the VMs controlled by compute manager 443. Compute manager 443 may manage the compute aspects, as well as the orchestration of the networking resources and the storage resources.

[0055] In some examples, compute manager 443 also communicates the networking resources needed to networking manager 445, which manages the networking resources, and communicates the storage resources needed to storage manager 444, which manages the storage resources. In some examples, networking manager 445 is configured to, upon request from compute manager 443, provide generic networking artifacts for the partially provisioned VM to be created, such as a default/placeholder virtual network and a default customer IP address. Networking manager 445 may also allocate a customer IP address to the default/placeholder virtual network, where the allocated customer IP address may be a placeholder customer IP address.

[0056] A MAC address and a NIC may also be allocated for the virtual network. In some examples, a virtual network is created and attached to the VM by networker manager 445 in the same manner as would normally occur in the creation of a VM, except that the VM as in internal, arbitrary network that will not be used by any customer, the network has no network rules because they are not needed, the customer IP address is simply a placeholder customer IP address, and also that some aspects of configuring the network may be skipped.

[0057] Because in some examples the configuration done during partial provisioning is a bare minimum configuration, and the placeholder virtual network will not actually be used by a customer, some aspects of configuring the virtual network for the VM may be skipped. For instance, in some examples, the virtual load balances for the virtual network are not configured to point to anything. In some examples, it is not necessary for the virtual load balances to point to anything because no customer will be using the placeholder virtual network.

[0058] In some examples, compute manager 443 also communicates storage resources needed to storage manager 444. In some examples, during the partial provisioning, only the OS disc storage is assigned during partial provisioning. In some examples, if a customer wishes additional storage, that is handled during the full configuration. In some examples, details of storage for the OS is a property that is not reconfigured, and so storage details options are included in the combination of different types of partially provisioned VMs that are created and managed by pool manager 441.

[0059] In some examples, actual creation and booting of the VM occurs in VM host 451. In some examples, during the boot process, VM host 451 causes the VM enters a state in which the VM actively seeks new configuration, so that the VM can be reconfigured with customer-specific settings once a configuration with the customer- specific settings is published. Also, in some examples, VM host 451 causes the VM to be created such that the VM includes an agent that is capable of causing reconfiguration the VM according to the user-specific settings in response to publication of a configuration with the customer-specific settings.

[0060] In some examples, VM host 451 executes a service called Instance Metadata Service that publishes a full configuration when available; in these examples, the agent may actively poll the Instance Metadata Service for the full configuration. In some examples, the manner in which the VM is partially configured and then enters into a state seeking full configuration varies depending on the OS type of the VM. In some examples, networking service 445 will provide the VM with the MAC address and physical IP address of the (placeholder) virtual network as normal. In some examples, the customer IP address is an address usable by a customer but which is not actual routable in the internal network, whereas the physical IP address is the IP address that is routable inside the internal network.

[0061] In some examples in which the VM has a Linux OS, the VM is booted, VM host 451 passes the VM a tag that indicates that the configuration is partial and not the final configuration. In some examples, when the VM is booted, the VM is configured with some but not all of the configurations— some configurations, including certain user- specific settings, are not done. However, in some examples, even though some user- specific settings are not done, or are done but given generic placeholder/default settings rather than user-specific settings, the VM sends a success message to VM host 451 indicating that the configuration is done. In some examples, because the configuration is not complete, in essence the VM is faking a success message so that the VM may remain in configuration mode, and configuration is completed when a full configuration with user-specified settings is available. In some examples, the success message is received by virtual machine host 451, and is sent from virtual machine host 451 to compute manager 443.

[0062] In response to the tag indicating that the configuration is only partial and not the final configuration, in some examples, the VM enters a state in which the VM polls VM host 451 for the new configuration. In some examples, the VM reads the tag to determine whether the configuration is partial or final. In some examples, a configuration with the tag is treated as a partial and not final configuration, and a configuration lacking the tag is treated as a final configuration. In some examples, the VM remains in this "partially booted" state, waiting for the complete configuration, until VM host 451 publishes a full configuration for the VM, at which point the VM's polling indicates that the full configuration is available.

[0063] In some examples in which the VM has a Windows OS, the VM is booted with a minimal configuration. In some examples, Windows itself cannot provision again after the minimal configuration performed in the first boot. Instead, in some examples, after setup finishes, VM host 451 causes a code extension to be installed and executed in the VM which causes the VM to keep running, and to enter a state in which the VM polls VM host 451 for the new configuration. In some examples, the VM remains in the polling state, waiting for the complete configuration, until VM host 451 publishes a full configuration for the VM, at which point the VM's polling indicates that the full configuration is available. In some examples, the code extension is capable of performing the reconfiguration to the full configuration.

[0064] In some examples, regardless of the OS type, after partially provisioning, in some examples, the VM is in a state in which it is polling for a full configuration to be used by which to reconfigure the VM. At this point, in some examples, a success message is sent to from the VM to VM host 451, from VM host 451 to compute manager 443, and compute manager 443 sends the success message to pool manager 442. At this point, in some examples, the VM is in the pool of partially provisioned VMs managed by VM pool manager 442.

[0065] Resource manager 441 may receive requests for VMs to customers, and may manage such requests. In some examples, customers may communicate with system 400 via a portal, and the portal may communicate requests from customer to resource manager 441. In response to customer request(s) for VM(s), resource manager 441 may send a request to compute manager 443 to deploys VMs. In response to the request from resource manager 441, compute manager 443 may communicate with VM pool manager 442 to determine from VM pool manager 442 whether or not there are existing partially provisioned VMs pooled by VM pool manger 442 that meet the required criteria. In some examples, if not, VMs will be created from scratch to meet the request.

[0066] If, however, there are available partially provisioned VMs in the VM pool managed by VM pool manager 442, then, in some examples, each partially provisioned VM is reconfigured to meet user-specific settings required based on the VMs requested, as follows for each VM in some examples. Compute manager 443 may send a request to storage manager 444 to cause corresponding storage artifacts to move their association from the platform to the particular customer. Such storage artifacts may include, for example, the disk on which the OS will be copied to and in which the OS will run, and any additional storage requested by the customer. By moving the association of the storage artifacts to the customer, in some examples, the customer has access to and can manage the storage artifacts, including, for example, the disk on which the OS will run.

[0067] Compute manager 443 may also request that certain storage artifacts be modified and/or reconfigured and/or created based on the user-specific settings. For example, the customer may have requested additional storage, which may be created and then associated with the particular customer. Compute manager 443 may also move corresponding compute artifacts, associated with the user-specific compute settings, to the particular customer. In this way, in some examples, the customer has access to and can manage the compute artifacts, including the VM itself. Compute manager 443 may also cause certain compute artifacts to be modified and/or reconfigured based on the user- specific settings.

[0068] An example of modifying and/or reconfiguring a compute artifact based on user-specific settings is changing the machine name based on the user-specific compute settings. A default/placeholder machine name may have been given to the partially provisioned VM during partial configuration in order to complete the initial, partial configuration. However, as part of the full configuration of the VM based on the user- specific settings, the user may have requested a VM with a particular machine name. Compute manager 443 may modify the machine name based on the user-specific settings. The changes in association of compute, network, and storage artifacts may be

accomplished with changes to the internal data structures— metadata changes to move the artifacts from the platform tenant to the customer tenant. A customer may have a particular subscription associated with the customer and the customer's subscription, where the customer subscription is used as a logical unit by which all of the virtual machines are included for the customer. Artifacts may be moved from the platform tenant to the customer subscription by updating the internal data structures including updating the corresponding metadata to reflect the re-association from the platform tenant to the customer's account.

[0069] Compute manager 443 may also send a request to networking manager 445 to cause corresponding networking artifacts to move their association from the platform to the particular customer, as well as for networking artifacts to be modified and/or reconfigured and/or created. For example, the partially configured VM may have a default placeholder virtual network, and the customer may wish for the VM to have a particular virtual network. Networking manager 445 may create a networking moniker by which to refer to the virtual network, so that compute manager can and need only refer to the new virtual network based on the network moniker assigned to the new virtual network. In some examples, networking manager 445 creates the requested virtual network, and associates the created virtual network with the customer so that the customer has access to and can manage the virtual network. Networking manager 445 may also configure any network rules requested by the customer, including rules for the network interface controller (NIC) and the media control access (MAC) address.

[0070] Networking manager 445 may create a new virtual network for the VM during reconfiguration, and remap to a new customer IP address requested by the customer, while reusing both the MAC address and the physical IP address of the VM prior to reconfiguration. In some examples, networking manager 445 determines which MAC address is already being used by the partially provisioned VM, and then re-uses the same MAC address for the VM during reconfiguration. The networking manager may include a directory service that maps the customer IP address to the physical IP address.

In some examples, when reconfiguring the VM for the new virtual network, networking manager 445 updates the directory service to map the customer-provided customer IP address for the new virtual network to the physical IP address (of the virtual network) that is being reused. Networking manager 445 may also reprogram the virtual load balances to point to the correct machines. Network manager 445 may also apply the virtual network to the VM. Networking manager 445 may send a success message to compute manager 443 when the networking aspects are complete.

[0071] In some examples, after the modifications, reconfigurations, creations, and/or re-associations to be performed outside the VM host 451 are complete, compute manager 442 communicates the reconfiguration information to VM host 451. In some examples, a networking agent in VM host 451 receives the information, and in response to receiving the information, reprograms drivers in VM host 451. In some examples, the networking agent in VM host 451 reprograms the drivers for the route remapping based on the new customer IP address. Next, in some examples, the networking agent in VM host 451 instructs an agent in the VM to retrigger DHCP. This agent in the VM may be the same agent discussed above that is polling the Instance Metadata Service for the configuration file. The manner in which the agent in the VM retriggers DHCP may depend upon the OS type of the VM.

[0072] In some examples, if the OS type of the VM is Windows, the agent in the VM may "bounce" the NIC— i.e., cause the NIC to momentarily disconnect and then reconnect, for example, by using a hypervisor VMSwitch exposed input/output control. In some examples, it is only necessary for the NIC to be disconnected for a few milliseconds, and this will cause DHCP to retrigger. In some examples, in a Windows based VM, the inbuilt DHCP client may detect link state change and automatically trigger DHCP, e.g in response to the link state change. The NIC disconnect / re-connect may be represented in the VM as a link state flap.

[0073] If the OS type is Linux, a NIC disconnect / re-connect may also be done. Another agent running inside the VM may continuously poll for this link state change, and may trigger a DHCP renewal sequence in response to detection of a link state change. In some examples, this polling is done for Linux but not for Windows. An agent on the node may trap this DHCP renewal request (e.g., through VMSwitch) and respond to the VM with network information for the new state (such as an IP address, DNS information, gateway/routing information, etc.). In response to receiving this new information, the DHCP client may provision this new information, e.g., and "bring" the VM to the new network.

[0074] In some examples, as discussed above, networking agent 445 causes the DHCP to retrigger by sending an instruction to the agent in the VM for the agent in the VM to retrigger the DHCP. In other examples, networking agent 445 may cause the DHCP to retrigger in some other manner, such as networking agent 445 itself causing the DHCP to retrigger, through instruction some other component of VM host 451 to retrigger the DHCP, or in some other suitable manner causing the DHCP to retrigger.

[0075] The network agent may communicate to a compute agent in VM host 451 after the DHCP retrigger has been completed. The compute agent in VH host 451 may then generate a file with the new configuration, and then publish the new configuration via the Instance Metadata Service in VM host 451, so that the new configuration is available to be polled by the partially configured VM, which is in a state of polling the Instance Metadata Service, for the new configuration, and the polling will be successful once the new configuration is published by the Instance Metadata Service.

[0076] The agent on the VM may then accept the user-specific settings associated with the reconfiguration requests, including user-specific networking settings, and then apply those user-specific settings, so that networking and possibly other aspects of the VM are reconfigured accordingly. In this way, in some examples, the partially provisioned VM becomes reconfigured based on the user-specific settings.

[0077] The manner in which the reconfiguration of the VM happens may depend in the OS type of the VM in some examples.

[0078] For instance, in some examples, if the OS type of the VM is Linux, the reconfiguration may be completed at this time. In some examples, the VM was left in a "partially booted" state, waiting for the complete configuration, and the configuration is allowed to finish now that the full configuration has been received, using the newly received full configuration.

[0079] In some examples, if the OS type is Windows, Windows cannot perform the configuration again, or remain in a partially booted state. Instead, in some examples, the same code extension that caused the VM to enter a state in which it polls VM host 451 for the new configuration may cause the VM to be reconfigured based on the full configuration, by in essence using the same configuration process normally used by Windows, except that the configuration is performed by the code extension rather than by Windows.

[0080] After the reconfiguration is successfully completed, the VM may send a success message to VM host 451 indicating that the reconfiguration is successful. VM host 451 may then communicate the success message to compute manager 443. Compute manager 443 may then communicate the success message to resource manager 441, which may in turn communicate the success message to the customer portal, which may in turn communicate the success to the customer. In some examples, use of the re-configured VM may then be tracked, and success or failure of the use of the re-configured VM may be reported, and appropriate actions may be taken based on the success or failure of the use of the re-configured VM.

Illustrative Process

[0081] For clarity, the processes described herein are described in terms of operations performed in particular sequences by particular devices or components of a system. However, it is noted that other processes are not limited to the stated sequences, devices, or components. For example, certain acts may be performed in different sequences, in parallel, omitted, or may be supplemented by additional acts or features, whether or not such sequences, parallelisms, acts, or features are described herein.

Likewise, any of the technology described in this disclosure may be incorporated into the described processes or other processes, whether or not that technology is specifically described in conjunction with a process. The disclosed processes may also be performed on or by other devices, components, or systems, whether or not such devices, components, or systems are described herein. These processes may also be embodied in a variety of ways. For example, they may be embodied on an article of manufacture, e.g., as processor-readable instructions stored in a processor-readable storage medium or be performed as a processor-implemented process. As an alternate example, these processes may be encoded as processor-executable instructions and transmitted via a

communications medium.

[0082] FIGs. 5A-5B are a flow diagram illustrating an example process (580) that may be performed, e g., by VM pool manager 342 of FIG. 3 or VM pool manager 442 of FIG. 4.

[0083] In the illustrated example, step 581 occurs first. At step 581, in some examples, categories of virtual machines are selected from a plurality of categories of virtual machines. As shown, step 582 occurs next in some examples. At step 582, in some examples, for each selected category of virtual machine, a cardinality of virtual machines of the selected category that are requested for provisioning is recorded over time. "Cardinality" refers to how many VMs of the selected category are requested.

[0084] As shown, step 583 occurs next in some examples. At step 583, in some examples, for each selected category of virtual machine, a prediction algorithm is used to predict a cardinality of virtual machines for the selected category to be requested in the future, such that the prediction algorithm weighs under-prediction of the cardinality of virtual machines as costlier than over-prediction of the cardinality of virtual machines. As shown, step 584 occurs next in some examples. At step 584, in some examples, for the selected categories of virtual machines, an error for the predicted cardinalities of virtual machines for the selected categories is determined.

[0085] As shown, step 585 occurs next in some examples. At step 585, in some examples, the prediction algorithm is updated over time based on the determined error.

As shown, step 586 occurs next in some examples. At step 586, in some examples, an adjustment for the predicted cardinalities for virtual machines for the selected categories is performed.

[0086] As shown, step 587 occurs next in some examples. At step 587, in some examples, for each selected category of virtual machine, a cardinality of virtual machines of the selected category of virtual machines are composed and booted with generic virtual machine artifacts such that the cardinality of virtual machines of the selected categories is the adjusted predicted cardinality of requested virtual machines for the selected category. As shown, step 588 occurs next in some examples. At step 588, in some examples, the booted virtual machines are caused to enter a state in which the booted virtual machines are polling for a configuration with user-specific compute settings and user-specific networking settings.

[0087] The process may then proceed to a return block, where other processing is resumed.

Conclusion

[0088] While the above Detailed Description describes certain examples of the technology, and describes the best mode contemplated, no matter how detailed the above appears in text, the technology can be practiced in many ways. Details may vary in implementation, while still being encompassed by the technology described herein. As noted above, particular terminology used when describing certain features or aspects of the technology should not be taken to imply that the terminology is being redefined herein to be restricted to any specific characteristics, features, or aspects with which that terminology is associated. In general, the terms used in the following claims should not be construed to limit the technology to the specific examples disclosed herein, unless the Detailed Description explicitly defines such terms. Accordingly, the actual scope of the technology encompasses not only the disclosed examples, but also all equivalent ways of practicing or implementing the technology.