Installation guide

Table Of Contents
3 Select a shares value, which represents a relative metric for allocating CPU capacity.
Option Description
Shares
The values Low, Normal, High, and Custom are compared to the sum of all
shares of all virtual machines on the server and, on ESX/ESXi hosts, the
service console. Share allocation symbolic values can be used to configure
their conversion into numeric values.
Reservation
Guaranteed CPU allocation for this virtual machine.
Limit
Upper limit for this virtual machine’s CPU allocation. Select Unlimited to
specify no upper limit.
For more information on share values, see the Resource Management Guide.
4 Click OK to save your changes.
The Virtual Machine Properties dialog box closes.
Advanced CPU Settings
The Advanced CPU Resources panel of the Virtual Machine Properties dialog box lets you set low-level options
that involve scheduling the virtual machine processing to physical processor cores and hyperthreads.
This panel does not appear for virtual machines in a DRS cluster or when the host has only one processor core
and no hyperthreading.
NOTE Hyperthreading technology allows a single physical processor to behave like two logical processors.
The processor can run two independent applications at the same time. While hyperthreading does not double
the performance of a system, it can increase performance by better utilizing idle resources. For detailed
information about hyperthreading and its use in vSphere, see the Resource Management Guide (select Help >
Manuals).
ESX generally manages processor scheduling well, even when hyperthreading is enabled. The settings on this
page are useful only for fine-grained tweaking of critical virtual machines.
The Hyperthreading Sharing option provides detailed control over whether a virtual machine should be
scheduled to share a physical processor core (assuming hyperthreading is enabled on the host at all).
The Scheduling Affinity option allows fine-grained control over how virtual machine CPUs are distributed
across the host's physical cores (and hyperthreads if hyperthreading is enabled).
Change Advanced CPU Settings of a Virtual Machine
Set the hyperthreaded core sharing mode for a virtual machine's advanced CPU settings in the Resource tab
of the Virtual Machine Properties dialog box.
Procedure
1 Click the Resources tab.
2 Select Advanced CPUin the Settings list.
vSphere Basic System Administration
156 VMware, Inc.