An allocation model determines how and when the allocated provider virtual data center (VDC) compute and memory resources are committed to the organization VDC.

The following table shows the vSphere resource distribution settings at the virtual machine (VM) or resource pool level based on the organization VDC allocation model.
Flex Allocation Model Elastic Allocation Pool Model Non-Elastic Allocation Pool Model Pay-As-You-Go Model Reservation Pool Model
Elastic Based on the organization VDC configuration. Yes No Yes No
vCPU Speed If a VM CPU limit is not defined in a VDC compute policy, vCPU speed might impact the VM CPU limit within the VDC. Impacts the number of running vCPUs in the Organization VDC. Not Applicable Impacts VM CPU Limit Not Applicable
Resource Pool CPU Limit Organization VDC CPU limit apportioned based on the number of VMs in the resource pool. Organization VDC CPU allocation Organization VDC CPU allocation Unlimited Organization VDC CPU allocation
Resource Pool CPU Reservation Organization VDC CPU reservation is apportioned based on the number of vCPUs in the resource pool. Organization VDC CPU reservation equals the organization VDC CPU allocation times the CPU guarantee. Sum of powered on VMs and equals the CPU guarantee times the vCPU speed, times the number of vCPUs. Organization VDC CPU allocation times the CPU guarantee None, expandable Organization VDC CPU allocation
Resource Pool Memory Limit Organization VDC memory limit is apportioned based on the number of VMs in the resource pool. Unlimited Organization VDC RAM allocation Unlimited Organization VDC RAM allocation
Resource Pool Memory Reservation Organization VDC RAM reservation is apportioned based on the number of VMs in the resource pool. The organization VDC RAM reservation equals the organization VDC RAM allocation times the RAM guarantee. Sum of RAM guarantee times vRAM of all powered-on VMs in the resource pool. The resource pool RAM reservation is expandable. Organization VDC RAM allocation times the RAM guarantee None, expandable Organization VDC RAM allocation
VM CPU Limit Based on the VDC Compute policy of the VM. Unlimited Unlimited vCPU speed times the number of vCPUs Custom
VM CPU Reservation Based on the VDC Compute policy of the VM. 0 0 Equals the CPU speed times the vCPU speed, times the number of vCPUs. Custom
VM RAM Limit Based on the VDC Compute policy of the VM. Unlimited Unlimited vRAM Custom
VM RAM Reservation Based on the VDC Compute policy of the VM. 0 Equals vRAM times RAM guarantee plus RAM overhead. Equals vRAM times RAM guarantee plus RAM overhead. Custom