第 7 章 Using Topology Manager
Topology Manager collects hints from the CPU Manager, Device Manager, and other Hint Providers to align pod resources, such as CPU, SR-IOV VFs, and other device resources, for all Quality of Service (QoS) classes on the same non-uniform memory access (NUMA) node.
Topology Manager uses topology information from collected hints to decide if a pod can be accepted or rejected on a node, based on the configured Topology Manager policy and Pod resources requested.
Topology Manager is useful for workloads that use hardware accelerators to support latency-critical execution and high throughput parallel computation.
To use Topology Manager you must use the CPU Manager with the static policy. For more information on CPU Manager, see Using CPU Manager.
7.1. Topology Manager policies
Topology Manager aligns Pod resources of all Quality of Service (QoS) classes by collecting topology hints from Hint Providers, such as CPU Manager and Device Manager, and using the collected hints to align the Pod resources.
To align CPU resources with other requested resources in a Pod spec, the CPU Manager must be enabled with the static CPU Manager policy.
Topology Manager supports four allocation policies, which you assign in the cpumanager-enabled custom resource (CR):
nonepolicy- This is the default policy and does not perform any topology alignment.
best-effortpolicy-
For each container in a pod with the
best-efforttopology management policy, kubelet calls each Hint Provider to discover their resource availability. Using this information, the Topology Manager stores the preferred NUMA Node affinity for that container. If the affinity is not preferred, Topology Manager stores this and admits the pod to the node. restrictedpolicy-
For each container in a pod with the
restrictedtopology management policy, kubelet calls each Hint Provider to discover their resource availability. Using this information, the Topology Manager stores the preferred NUMA Node affinity for that container. If the affinity is not preferred, Topology Manager rejects this pod from the node, resulting in a pod in aTerminatedstate with a pod admission failure. single-numa-nodepolicy-
For each container in a pod with the
single-numa-nodetopology management policy, kubelet calls each Hint Provider to discover their resource availability. Using this information, the Topology Manager determines if a single NUMA Node affinity is possible. If it is, the pod is admitted to the node. If a single NUMA Node affinity is not possible, the Topology Manager rejects the pod from the node. This results in a pod in a Terminated state with a pod admission failure.
