VMware vCloud® Director ™ Resource Allocation Models ppt

VMware vCloud ® Director ™ Resource Allocation Models TECHNICAL MARKETING DOCUMENTATION V 1.0/UPDATED AUGUST 2012 VMware vCloud Director Resource Allocation Models TECHNICAL WHITE PAPER / 2 Table of Contents PurposeandOverview  TargetAudience  InterpretingThisDocument  ReferenceMaterial  ResourceManagementConstructs  vCloudDirectorConstructs  vSphereResourceConstructs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vCloudDirectorArchitecture  ArchitectingtheProviderVirtualDatacenter  OrganizationVirtualDatacenters  AllocationModels  Pay-As-You-GoModelSettings  ExpandableReservation  ReservationPoolModelSettings  ExpandableReservation  CustomPer–VirtualMachineResourceSettings  AllocationPoolModelSettings  ExpandableReservation  ReviewofResourceDistribution  VirtualMachineDistributiononStorageLevel  Pay-As-You-GoModel  ReservationPoolModel  AllocationPoolModel  vCloudAllocationModelsinPractice  ConsumerFunctionalRequirements  Pay-As-You-GoModel  ReservationPoolModel  AllocationPoolModel  CatalogOrganizationVirtualDatacenter  vCloudSystemVirtualDatacenter  TestCases  SingleAllocationModelTests  SingleAllocationModel–Pay-As-You-Go  SingleAllocationModel–ReservationPool  SingleAllocationModel–AllocationPool  VMware vCloud Director Resource Allocation Models TECHNICAL WHITE PAPER / 3 MultipleAllocationModels  DefaultResourceAllocationSettingsTest  CustomResourceAllocationSettingsTest  AbouttheAuthors  TECHNICAL WHITE PAPER / 4 VMware vCloud Director Resource Allocation Models Purpose and Overview VMware vCloud® Director™ enables users to build a private cloud–based infrastructure as a service (IaaS) oering within their organization. By providing a secure, on-demand ability for end users to deploy workloads, companies can realize a level of agility previously thought impossible. Resource design for vCloud Director involves examining requirements to determine how best to partition and organize resources. With the commoditization of infrastructure resources, the ability to scale them becomes increasingly important. When designing for vCloud Director, keep in mind that the ultimate consumers of the product are the end users of the system. Taking a top-down approach to vCloud Director design necessitates an understanding of the new abstractions introduced in the vCloud API and how they map to traditional VMware vSphere® objects. This paper was developed to provide additional insight and information as to how vCloud Director allocation models relate to vSphere resource management. The paper reviews and discusses various design considerations and operational procedures. Target Audience The target audience of this document is individuals with a technical background who will be designing, deploying or managing a vCloud Director infrastructure. This includes but is not limited to technical consultants, infrastructure architects, IT managers, implementation engineers, partner engineers, sales engineers and customer sta. This solution brief is not intended to replace the VMware vCloud Architecture Toolkit. It instead is meant to supplement knowledge and provide additional information. As vCloud Director implementations have evolved, there has been a noticeable increase in provider and consumer confusion about the vCloud Director allocation concepts as related to vSphere. Interpreting This Document The overall structure of this case study is, for the most part, self-explanatory. However, throughout this document there are key points of particular importance that will be highlighted to the user. These points will be identified with one of the following labels: •NOTE–Generalpointofimportanceorafurtherexplanationwithinaparticularsection •EXAMPLE–Aspecicusecasetoillustrateaconceptwithinasection The authors of this document assume that the reader is familiar with vCloud Director, vSphere, VMware® vCenter Server™, VMware vSphere High Availability (vSphere HA), VMware vSphere Distributed Resource Scheduler™ (vSphere DRS) and VMware vSphere Storage DRS™ technology and terminology. Reference Material Reading the following documents that have been used to develop this solution brief is recommended: •vSphere5ResourceManagementGuide •VMwarevCloudArchitectureToolkit  TECHNICAL WHITE PAPER / 5 VMware vCloud Director Resource Allocation Models Resource Management Constructs vCloud Director introduces logical constructs to facilitate multitenancy and provide interoperability between vCloud Director instances built to the vCloud API standard. vCloud Director Constructs Table 1 describes the logical constructs in vCloud Director that are used to abstract the underlying vSphere constructs. VCLOUD DIRECTOR CONSTRUCT DESCRIPTION Organization An organization is the unit of multitenancy that represents a single logical security boundary. An organization contains users, virtual datacenters and networks. Provider Virtual Datacenter A provider virtual datacenter (VDC) is a grouping of compute and storage resources from a single vCenter Server instance. A provider VDC consists of a pool of physical compute resources and one or more datastores. Multiple organizations can share provider VDC resources. Organization Virtual Datacenter An organization virtual datacenter is a subgrouping of compute and storage resources allocated from a provider VDC and assigned to a single organization. An organization VDC is provisioned resources using vCloud Director resource allocation models. These are represented in vSphere by “resource pools,” defined in Table 2. Resource Allocation Models Resource allocation models define how resources are provisioned to an organization’s VDC from the provider VDC. They also define how resources can be used when deploying virtual applications (vApps) within the organization VDC. vApp A vApp is a container for a distributed software solution and is the standard unit of deployment in vCloud Director. A vCloud Director vApp is very dierent from a vSphere vApp in the manner it is instantiated and consumed in vCloud Director. It enables power operations to be defined and specifically ordered. It consists of one or more virtual machines and can be imported or exported as an OVF package. A vCloud vApp can have additional vCloud-specific constructs such as vApp networks. Table 1. vCloud Director Constructs TECHNICAL WHITE PAPER / 6 VMware vCloud Director Resource Allocation Models vSphere Resource Constructs Table 2 describes the resource management constructs in vSphere. VSPHERE RESOURCE CONSTRUCT DESCRIPTION Distributed Resource Scheduler Cluster A vSphere DRS cluster is a collection of vSphere hosts with shared resources. It must be created first to obtain the benefits of cluster-level resource management, such as resource pools. Resource Pools A resource pool is a logical abstraction of physical resources for flexible management of resources. Resource pools can be grouped into hierarchies and used to hierarchically partition available CPU and memory resources. Reservation A reservation specifies the guaranteed minimum physical resource allocation for a virtual machine or resource pool. A power-on operation of a virtual machine (via vCenter Server or directly accessing the vSphere host with VMware vSphere Client™) will succeed only if there are enough unreserved resources to satisfy the reservation needed by the virtual machine. The server guarantees that amount even when the physical server is heavily loaded. The reservation is expressed in physical units (megahertz or megabytes). Limit Limit specifies an upper boundary for CPU or memory resources that can be allocated to a virtual machine or resource. A server can allocate more than the reservation to a virtual machine, but it never allocates more than the limit, even if there are unused resources on the system. The limit is expressed in concrete units (megahertz or megabytes). The default value for limits is “unlimited.” When the memory value is unlimited, the amount of memory configured for the virtual machine when it was created becomes its eective limit. Shares Shares specify the relative importance of a virtual machine or resource pool. If a virtual machine has twice as many shares of a resource as another virtual machine, it is entitled to consume twice as much of that resource when these two virtual machines are competing for resources. Memory Overhead Reservation Memory overhead reservation is the amount of consumed memory being used for virtualization purposes. Overhead memory includes space reserved for the virtual machine frame buer and various virtualization data structures, such as shadow page tables. Table 2. vSphere Resource Management Constructs TECHNICAL WHITE PAPER / 7 VMware vCloud Director Resource Allocation Models vCloud Director Architecture The vSphere infrastructure provides the foundation of the vCloud Director architecture. Building a vCloud service requires an understanding of the individual constructs of the entire architecture. The vSphere layer provides a consumable set of resources available to the VMware vCloud environment and will present these resources to a provider VDC. The provider VDC supplies an abstraction layer for resources. As each organization VDC withdraws resources from its provider VDC, the provider VDC creates the association between the organization VDC and resources at the vSphere layer. The vCloud allocation model defined on each organization VDC dictates how the resources of the vSphere layer are consumed, and it influences the availability of resources to the other organization VDCs sharing the same provider VDC. O r g a n i z a t i o n V i r t u a l D a t a c e n t e r A l l o c a t i o n M o d e l P r o v i d e r V i r t u a l D a t a c e n t e r v S p h e r e R e s o u r c e s Construct Interdynamics Figure 1. Cycle of vSphere and vCloud Construct Interdynamics This interaction of vSphere and vCloud constructs determines the flexibility of the resource availability within the vCloud environment. And eventually it is the resource availability that drives the consolidation ratio of the organization VDCs within a provider VDC. The remaining chapters expand on the architecture of the provider VDC and how vCloud allocation models consume resources. TECHNICAL WHITE PAPER / 8 VMware vCloud Director Resource Allocation Models Architecting the Provider Virtual Datacenter A provider VDC is a collection and an abstraction of vSphere resources. Virtual datacenters deal with two types of resources: compute and storage. vSphere DRS clusters or resource pools provide the CPU and memory resources, while storage resources are provided by datastores. Abstracting these infrastructure resources into a single management construct enables the pooling of compute and storage resources of similar performance or availability levels that can be mapped to a specific service oering. EXAMPLE:DierentiationbyperformancemightbeaFlash-based(SSD)storagepoolforagoldproviderVDC asopposedtoaSATA-basedstoragepoolforabronzeproviderVDC. Cluster Storage Datastores Provider Virtual Datacenter Compute Resource Pool Figure 2. Provider VDC Resource Mapping A provider VDC can be mapped directly to a vSphere DRS cluster or to a resource pool within a vSphere DRS cluster. Provider VDC Resource Pool DRS Cluster Map to Figure 3. Mapping Provider VDC to Cluster or Resource Pool By mapping the provider VDC to a vSphere DRS cluster, all compute and storage resources are dedicated to the provider VDC. This enables ecient distribution and allocation of resources to various organizations. If additional resources are required, hosts and storage can be added to the vSphere DRS cluster. New physical resources added to the cluster are automatically integrated to the provider VDC. When the provider VDC is mapped to resource pool level, additional physical resources must be configured manually by updating the reservation and limits of the resource pool. The partitioning of cluster resources by mapping provider VDCs to resource pools increases the complexity of managing compute and storage resources. TECHNICAL WHITE PAPER / 9 VMware vCloud Director Resource Allocation Models NOTE:ItisavSpherebestpracticetoconnectdatastorestoallhostsinthecluster,enablingvSphereDRSto distributevirtualmachinesasoptimallyaspossible. vCloud Director utilizes vSphere resource pools to partition the resources of the provider VDC for each organization. If the provider VDC is mapped to a resource pool, only the reserved resources assigned to the parent resource pool is used and distributed among the organization VDCs. The resource pools belonging to dierent organization VDCs become children of the parent provider VDC resource pool. Organization Virtual Datacenters Organization VDCs are used by vCloud Director to partition provider VDCs. As mentioned previously, vCloud Director uses vSphere resource pools as the basic construct to partition these resources. An organization can have multiple organization VDCs, each utilizing resources from a dierent provider VDC oering dierent classes of service based on associated performance, availability and cost characteristics. A provider VDC can present its resources to multiple organization VDCs belonging to dierent organizations. Organization VDC Organization Customer 1 Gold Provider Bronze Provider Provider VDC Organization VDC Organization VDC Provider VDC Figure 4. Multiple Organization VDCs Each organization VDC is configured based on an allocation model. An allocation model defines how resources are allocated from the provider VDC. An organization VDC must be configured with one of the following three allocation models: •Pay-as-you-go •Allocation-pool •Reservation-pool TECHNICAL WHITE PAPER / 10 VMware vCloud Director Resource Allocation Models Allocation Models Organizations can consume resources from multiple organization VDCs using one of three resource allocation models: pay-as-you-go, allocation-pool and reservation-pool. Figure 5. Overview vCloud Director Allocation Model VCLOUD DIRECTOR RESOURCE SETTING VSPHERE RESOURCE SETTING Allocation Limit Guarantee Reservation vCPU speed Limit on CPU virtual machine level Table 3. Resource-Setting Taxonomy The distinction between each of the allocation models is in how resources are consumed. vCloud Director enables each allocation model to configure a guaranteed amount (reservation) and a maximum amount (limit) of physical resources that are available to the organization VDC. To guarantee physical resources, vSphere can set a reservation on resource pool level and virtual machine level. A limit is set on resource pool level and virtual machine level if a maximum amount of resources is defined in the organization VDC. Depending on the chosen allocation model, reservations and limits will be set on resource pool level, virtual machine level or both. [...].. .VMware vCloud Director Resource Allocation Models Virtual Machine–Level Settings Resource Pool–Level Settings Virtual Machine– and Resource Pool–Level Settings VM VM VM VM VM VM VM VM VM Resource Pool Resource Pool Resource Pool Pay-As-You-Go Model Reservation-Pool Model Allocation- Pool Model Figure 6 Overview of Allocation Models and vSphere Settings Each allocation model enables specifying allocation. .. WH ITE PAPE R / 17 VMware vCloud Director Resource Allocation Models Memory Limit Memory Reservation VM Virtual Machine–Level Settings Resource Pool–Level Settings VM VM Resource Pool Memory Limit Memory Reservation CPU Limit CPU Reservation Figure 17 Allocation Pool Model Default Settings CPU resources: The allocation pool model provides a recommendation to set the CPU limit on the resource pool level... sections contains the following resources SETTING CPU MEMORY Provider VDC 15GHz 50GB Table 4 Provider VDC Resources TECH N I C AL WH ITE PAPE R / 11 VMware vCloud Director Resource Allocation Models Pay-As-You-Go Model Settings The pay-as-you-go model provides the illusion of an unlimited resource pool This model maps to a resource pool with no configured reservations or limits Resources are committed only... configured without a CPU reservation TECH N I C AL WH ITE PAPE R / 1 8 VMware vCloud Director Resource Allocation Models Figure 19 Virtual Machine–Level CPU Resource Settings Memory resources: The allocation pool model provides a recommendation to set the CPU reservation on the resource pool level equal to 20 percent of the available resources from the provider VDC A limit is set identical to the configured... is disabled on both CPU and memory resources of the resource pool Review of Resource Distribution This section reviews the resource distribution concepts of all the vCloud Director allocation models The primary focus of these examples is on the distribution and consumption of memory resources The reason for the focus on memory is that when resource demand exceeds resource supply, the overhead and additional... Unreserved Memory Figure 22 Resource Distribution of Pay-As-You-Go Model TECH N I C AL WH ITE PAPE R / 21 VMware vCloud Director Resource Allocation Models Opportunistic allocation: The pay-as-you-go model enables configuring the CPU reservation on virtual machine level only and sets it by default to 0 percent Using the default results in opportunistic allocation of CPU resources by the resource pool and virtual... PAPE R / 3 4 VMware vCloud Director Resource Allocation Models The unreserved resources belonging to the provider VDC function as burstable space for the allocation pool Organization VDCs that are configured for opportunistic allocation can compete for the unreserved resources The total required memory demand exceeds the current capacity of 50GB offered by the provider VDC Customer 1: The resource pool... WH ITE PAPE R / 35 VMware vCloud Director Resource Allocation Models The impact of the oversubscription on the burst space can have the following effect if all virtual machines are equally active and demand resources EXAMPLE: Resource pools of customers 2 and 3 are required to allocate resources for their virtual machines The resource pool of customer 3 demands more memory than the resource pool of customer... the imported template has preconfigured per–virtual machine resource settings, these settings will be maintained All subsequent vApps deployed from this template will be configured with the custom resource settings TECH N I C AL WH ITE PAPE R / 1 6 VMware vCloud Director Resource Allocation Models NOTE: Both pay-as-you-go and allocation pool models do not apply the template settings to new virtual machines... PAPE R / 20 VMware vCloud Director Resource Allocation Models TERM DESCRIPTION Opportunistic access Resource allocation based on priority and levels of contention Resources are allocated based on the relative share value Contention Resource demand exceeds resource supply Table 8 Resource Management Taxonomy Virtual Machine Distribution on Storage Level vCloud Director distributes virtual machines within . VMware vCloud ® Director ™ Resource Allocation Models TECHNICAL MARKETING DOCUMENTATION V 1.0/UPDATED AUGUST 2012 VMware vCloud Director Resource Allocation.  TECHNICAL WHITE PAPER / 4 VMware vCloud Director Resource Allocation Models Purpose and Overview VMware vCloud® Director enables users to build a private