website/content/zh/docs/tasks/manage-hugepages/scheduling-hugepages.md

---
reviewers:
- derekwaynecarr
title: 管理巨页（HugePages）
content_template: templates/task
---
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---
reviewers:
- derekwaynecarr
title: Manage HugePages
content_template: templates/task
---
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{{< feature-state state="stable" >}}

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Kubernetes supports the allocation and consumption of pre-allocated huge pages
by applications in a Pod as a **GA** feature. This page describes how users
can consume huge pages and the current limitations.
--->
作为 **GA** 特性，Kubernetes 支持在 Pod 应用中使用预先分配的巨页。本文描述了用户如何使用巨页，以及当前的限制。

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1. Kubernetes nodes must pre-allocate huge pages in order for the node to report
   its huge page capacity. A node may only pre-allocate huge pages for a single
   size.

The nodes will automatically discover and report all huge page resources as a
schedulable resource.
--->
1. 为了使节点能够上报巨页容量，Kubernetes 节点必须预先分配巨页。每个节点只能预先分配一种特定规格的巨页。

节点会自动发现全部巨页资源，并作为可供调度的资源进行上报。

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## API

<!--
Huge pages can be consumed via container level resource requirements using the
resource name `hugepages-<size>`, where size is the most compact binary notation
using integer values supported on a particular node. For example, if a node
supports 2048KiB page sizes, it will expose a schedulable resource
`hugepages-2Mi`. Unlike CPU or memory, huge pages do not support overcommit. Note
that when requesting hugepage resources, either memory or CPU resources must
be requested as well.
--->

用户可以通过在容器级别的资源需求中使用资源名称 `hugepages-<size>` 来使用巨页，其中的 size 是特定节点上支持的以整数值表示的最小二进制单位。 例如，如果节点支持 2048KiB 的页面规格， 它将暴露可供调度的资源 `hugepages-2Mi`。 与 CPU 或内存不同，巨页不支持过量使用（overcommit）。
注意，在请求巨页资源时，还必须请求内存或 CPU 资源。

```yaml
apiVersion: v1
kind: Pod
metadata:
  generateName: hugepages-volume-
spec:
  containers:
  - image: fedora:latest
    command:
    - sleep
    - inf
    name: example
    volumeMounts:
    - mountPath: /hugepages
      name: hugepage
    resources:
      limits:
        hugepages-2Mi: 100Mi
        memory: 100Mi
      requests:
        memory: 100Mi
  volumes:
  - name: hugepage
    emptyDir:
      medium: HugePages
```

<!--
- Huge page requests must equal the limits. This is the default if limits are
  specified, but requests are not.
- Huge pages are isolated at a pod scope, container isolation is planned in a
  future iteration.
- EmptyDir volumes backed by huge pages may not consume more huge page memory
  than the pod request.
- Applications that consume huge pages via `shmget()` with `SHM_HUGETLB` must
  run with a supplemental group that matches `proc/sys/vm/hugetlb_shm_group`.
- Huge page usage in a namespace is controllable via ResourceQuota similar
to other compute resources like `cpu` or `memory` using the `hugepages-<size>`
token.
--->

- 巨页的资源请求值必须等于其限制值。该条件在指定了资源限制，而没有指定请求的情况下默认成立。
- 巨页是被隔离在 pod 作用域的，计划在将来的迭代中实现容器级别的隔离。
- 巨页可用于 EmptyDir 卷，不过 EmptyDir 卷所使用的巨页数量不能够超出 Pod 请求的巨页数量。
- 通过带有 `SHM_HUGETLB` 的 `shmget()` 使用巨页的应用，必须运行在一个与
   `proc/sys/vm/hugetlb_shm_group` 匹配的补充组下。
- 通过 ResourceQuota 资源，可以使用 `hugepages-<size>` 标记控制每个命名空间下的巨页使用量，
  类似于使用 `cpu` 或 `memory` 来控制其他计算资源。

<!--
## Future

- Support container isolation of huge pages in addition to pod isolation.
- NUMA locality guarantees as a feature of quality of service.
- LimitRange support.
--->

## 待实现的特性

- 在 pod 级别隔离的基础上，支持巨页在容器级别的隔离。
- 作为服务质量特性，保证巨页的 NUMA 局部性。
- 支持 LimitRange 。

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