Information Technology Reference
In-Depth Information
resources are allocated. Next, we'll describe how these mechanisms are used to control memory
allocation.
Controlling Memory Allocation
Like all physical resources, memory is a i nite resource. The advanced memory-management tech-
nologies in ESXi help with the efi cient use of this i nite resource by making it go farther than it
normally would go. For i ner-grained control over how ESXi allocates memory, though, administra-
tors must turn to the use of the three mechanisms listed previously: reservations, shares, and lim-
its. Figure 11.3 shows these three settings in the Virtual Machine Properties dialog box for a VM.
The steps for editing a Reservation, Limit, or Shares value for either memory or CPU are the
same. Storage I/O and network I/O are handled a bit differently, so we'll discuss those in the appro-
priate sections later in this chapter. Storage I/O is covered in the section “Controlling Storage I/O
Utilization,” and network I/O is discussed in the section “Regulating Network I/O Utilization.”
Perform the following steps to edit a VM's memory or CPU Reservation, Limit, or Shares value:
1.
Use the Web Client to connect to a vCenter Server instance.
2.
Navigate to either the Hosts And Clusters or VMs And Templates view, then drill down
through the inventory to i nd the VM to be edited.
3.
Select the VM, and select the Edit Settings option in the content area.
4.
On the Virtual Hardware tab, click the triangle next to the CPU or Memory item.
5.
Adjust the Shares, Reservation, and Limit values as desired.
Figure 11.3
vSphere supports
the use of reserva-
tions, shares, and
limits for con-
trolling memory
allocation.
