> For the complete documentation index, see [llms.txt](https://book.bsdcn.org/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://book.bsdcn.org/man/man4/mac_priority.4.md).

# mac\_priority.4

`mac_priority` — 非\_root\_用户的调度特权策略

## 名称

`mac_priority`

## 概要

要将 mac\_priority 策略编译进内核，请在内核配置文件中加入以下行：

> options MAC options MAC\_PRIORITY

或者，要在引导时加载 mac\_priority 策略模块，请在内核配置文件中加入以下行：

> options MAC

并在 loader.conf(5) 中加入：

```sh
mac_priority_load="YES"
```

## 描述

`mac_priority` 策略根据 [group(5)](/man/man5/group.5.md) 成员资格授予调度特权。“realtime”组（gid 47）中的用户或进程允许以实时调度优先级运行线程和进程。“idletime”组（gid 48）中的用户或进程允许以空闲调度优先级运行线程和进程。

在 `mac_priority` 实时策略启用时，特权用户可以使用 rtprio(1) 工具以实时优先级启动进程。特权应用程序可以通过 rtprio(2) 系统调用将线程和进程提升为实时优先级。

在 idletime 策略启用时，特权用户可以使用 idprio(1) 工具以空闲优先级启动进程。特权应用程序可以通过 rtprio(2) 系统调用将线程和进程降级为空闲优先级。

### 授予的特权

实时策略向任何以实时组 ID 运行的进程授予以下内核特权：

**`PRIV_SCHED_RTPRIO`** **`PRIV_SCHED_SETPOLICY`**

idletime 策略授予的内核特权为：

**`PRIV_SCHED_IDPRIO`**

### 运行时配置

以下 [sysctl(8)](/man/man8/sysctl.8.md) MIB 可用于微调此 MAC 策略。所有 [sysctl(8)](/man/man8/sysctl.8.md) 变量也可在 loader.conf(5) 中设置为 [loader(8)](/man/man8/loader.8.md) 可调参数。

**`security.mac.priority.realtime`** 启用实时策略。（默认值：1。）

**`security.mac.priority.realtime_gid`** realtime 组的数字 gid。（默认值：47。）

**`security.mac.priority.idletime`** 启用 idletime 策略。（默认值：1。）

**`security.mac.priority.idletime_gid`** idletime 组的数字 gid。（默认值：48。）

## 参见

idprio(1), rtprio(1), rtprio(2), [mac(4)](/man/man4/mac.4.md)

## 历史

MAC 首次出现于 FreeBSD 5.0，`mac_priority` 首次出现于 FreeBSD 13.1。


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://book.bsdcn.org/man/man4/mac_priority.4.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.