6.7

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You can specify the following options.
NUMA Node Affinity When you set this option, NUMA can schedule a virtual machine only on
the nodes specified in the affinity.
CPU Affinity When you set this option, a virtual machine uses only the processors
specified in the affinity.
Memory Affinity When you set this option, the server allocates memory only on the specified
nodes.
A virtual machine is still managed by NUMA when you specify NUMA node affinity, but its virtual CPUs
can be scheduled only on the nodes specified in the NUMA node affinity. Likewise, memory can be
obtained only from the nodes specified in the NUMA node affinity. When you specify CPU or memory
affinities, a virtual machine ceases to be managed by NUMA. NUMA management of these virtual
machines is effective when you remove the CPU and memory affinity constraints.
Manual NUMA placement might interfere with ESXi resource management algorithms, which distribute
processor resources fairly across a system. For example, if you manually place 10 virtual machines with
processor-intensive workloads on one node, and manually place only 2 virtual machines on another node,
it is impossible for the system to give all 12 virtual machines equal shares of systems resources.
Associate Virtual Machines with Specific Processors
You might be able to improve the performance of the applications on a virtual machine by pinning its
virtual CPUs to fixed processors. This allows you to prevent the virtual CPUs from migrating across
NUMA nodes.
Procedure
1 Browse to the virtual machine in the vSphere Client.
a To find a virtual machine, select a data center, folder, cluster, resource pool, or host.
b Click the VMs tab.
2 Right-click the virtual machine and click Edit Settings.
3 Select the Virtual Hardware tab, and expand CPU.
4 Under Scheduling Affinity, set the CPU affinity to the preferred processors.
Note You must manually select all processors in the NUMA node. CPU affinity is specified on a per-
processor, not on a per-node, basis.
vSphere Resource Management
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