linux下共享内存模块实现原理详解
1. 模块概述
shm 模块是一个专为实现高效的进程间通信而设计的模块。它巧妙结合了共享内存（Shared Memory）和事件通知机制（eventfd），为系统提供了低延迟、高带宽的数据传输能力，是连接不同进程的重要桥梁。
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接收进程
shm模块
发送进程
数据生成
写入共享内存
向eventfd写入数据长度
eventFD组件
epoll监控
读取eventfd数据
触发事件通知
从共享内存读取数据
广播数据事件
事件监听器
处理接收到的数据
2. 核心组件
2.1 组件结构
shm 模块由三个核心组件协同工作，共同实现高效的进程间通信：
| shm | 主类 | 对外提供统一接口，协调各组件工作流程 |
| eventFD | 辅助类 | 实现事件通知机制，监听数据就绪状态 |
| sharedMem | 底层组件 | 负责共享内存的创建、管理和数据读写 |
2.2 类图
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