CPU allocation

Ensure that the VMs that are hosting the Managers are allocated an optimal number of virtual CPUs (vCPUs). For the final testing of the Managers, VMware configured the VMs with four vCPUs, which is half the number of physical CPUs on each ESX host that was used in the testing.

The eight physical CPUs on an ESX host were implemented as two separate quad-core processors, where each “core” or “execution core” is a separate processor. The physical CPUs are enabled in the BIOS when an ESX host is booted.

For the discovery and monitoring of large network topologies, VMware recommends the allocation of four vCPUs. For the discovery and monitoring of small to medium network topologies, VMware recommends the allocation of two vCPUs. Note that adding more vCPUs than necessary might adversely affect performance.

Here are some other CPU-related recommendations and considerations:

• Check that the hardware abstraction layer (HAL) or kernel for the VMs is configured to use more than one CPU.

• Check that adequate CPU is allocated to the VMs. See “Ensure adequate allocation of CPU and memory resources” on page 188 for details.

• Check the CPU performance for the VMs. See “Monitor CPU and memory performance” on page 188 for details.