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<ol class="chapter"><li class="chapter-item expanded affix "><li class="part-title">eBPF 入门开发实践教程</li><li class="chapter-item expanded "><a href="../0-introduce/index.html"><strong aria-hidden="true">1.</strong> eBPF 入门开发实践教程一:介绍 eBPF 的基本概念、常见的开发工具</a></li><li class="chapter-item expanded "><a href="../1-helloworld/index.html"><strong aria-hidden="true">2.</strong> eBPF 入门开发实践教程二Hello World基本框架和开发流程</a></li><li class="chapter-item expanded "><a href="../2-kprobe-unlink/index.html"><strong aria-hidden="true">3.</strong> eBPF 入门开发实践教程二:在 eBPF 中使用 kprobe 监测捕获 unlink 系统调用</a></li><li class="chapter-item expanded "><a href="../3-fentry-unlink/index.html"><strong aria-hidden="true">4.</strong> eBPF 入门开发实践教程三:在 eBPF 中使用 fentry 监测捕获 unlink 系统调用</a></li><li class="chapter-item expanded "><a href="../4-opensnoop/index.html"><strong aria-hidden="true">5.</strong> eBPF 入门开发实践教程四:在 eBPF 中捕获进程打开文件的系统调用集合,使用全局变量过滤进程 pid</a></li><li class="chapter-item expanded "><a href="../5-uprobe-bashreadline/index.html"><strong aria-hidden="true">6.</strong> eBPF 入门开发实践教程五:在 eBPF 中使用 uprobe 捕获 bash 的 readline 函数调用</a></li><li class="chapter-item expanded "><a href="../6-sigsnoop/index.html"><strong aria-hidden="true">7.</strong> eBPF 入门开发实践教程六:捕获进程发送信号的系统调用集合,使用 hash map 保存状态</a></li><li class="chapter-item expanded "><a href="../7-execsnoop/index.html"><strong aria-hidden="true">8.</strong> eBPF 入门实践教程七:捕获进程执行/退出时间,通过 perf event array 向用户态打印输出</a></li><li class="chapter-item expanded "><a href="../8-exitsnoop/index.html"><strong aria-hidden="true">9.</strong> eBPF 入门开发实践教程八:在 eBPF 中使用 exitsnoop 监控进程退出事件,使用 ring buffer 向用户态打印输出</a></li><li class="chapter-item expanded "><a href="../9-runqlat/index.html"><strong aria-hidden="true">10.</strong> eBPF 入门开发实践教程九:一个 Linux 内核 BPF 程序,通过柱状图来总结调度程序运行队列延迟,显示任务等待运行在 CPU 上的时间长度</a></li><li class="chapter-item expanded "><a href="../10-hardirqs/index.html"><strong aria-hidden="true">11.</strong> eBPF 入门开发实践教程十:在 eBPF 中使用 hardirqs 或 softirqs 捕获中断事件</a></li><li class="chapter-item expanded "><a href="../11-bootstrap/index.html"><strong aria-hidden="true">12.</strong> eBPF 入门开发实践教程十一:在 eBPF 中使用 bootstrap 开发用户态程序并跟踪 exec() 和 exit() 系统调用</a></li><li class="chapter-item expanded affix "><li class="part-title">eBPF入门实践教程</li><li class="chapter-item expanded "><a href="../13-tcpconnlat/index.html"><strong aria-hidden="true">13.</strong> eBPF入门实践教程使用 libbpf-bootstrap 开发程序统计 TCP 连接延时</a></li><li class="chapter-item expanded "><a href="../13-tcpconnlat/tcpconnlat.html"><strong aria-hidden="true">14.</strong> eBPF 入门实践教程:编写 eBPF 程序 tcpconnlat 测量 tcp 连接延时</a></li><li class="chapter-item expanded "><a href="../14-tcpstates/index.html"><strong aria-hidden="true">15.</strong> eBPF入门实践教程使用 libbpf-bootstrap 开发程序统计 TCP 连接延时</a></li><li class="chapter-item expanded "><a href="../15-tcprtt/index.html"><strong aria-hidden="true">16.</strong> eBPF 入门实践教程:编写 eBPF 程序 Tcprtt 测量 TCP 连接的往返时间</a></li><li class="chapter-item expanded "><a href="../16-memleak/index.html" class="active"><strong aria-hidden="true">17.</strong> eBPF 入门实践教程:编写 eBPF 程序 Memleak 监控内存泄漏</a></li><li class="chapter-item expanded "><a href="../17-biopattern/index.html"><strong aria-hidden="true">18.</strong> eBPF 入门实践教程:编写 eBPF 程序 Biopattern: 统计随机/顺序磁盘 I/O</a></li><li class="chapter-item expanded "><a href="../18-further-reading/index.html"><strong aria-hidden="true">19.</strong> 更多的参考资料</a></li><li class="chapter-item expanded "><a href="../19-lsm-connect/index.html"><strong aria-hidden="true">20.</strong> eBPF 入门实践教程:使用 LSM 进行安全检测防御</a></li><li class="chapter-item expanded "><a href="../20-tc/index.html"><strong aria-hidden="true">21.</strong> eBPF 入门实践教程:使用 eBPF 进行 tc 流量控制</a></li><li class="chapter-item expanded affix "><li class="part-title">bcc Guide</li><li class="chapter-item expanded "><a href="../bcc-documents/kernel-versions.html"><strong aria-hidden="true">22.</strong> BPF Features by Linux Kernel Version</a></li><li class="chapter-item expanded "><a href="../bcc-documents/kernel_config.html"><strong aria-hidden="true">23.</strong> Kernel Configuration for BPF Features</a></li><li class="chapter-item expanded "><a href="../bcc-documents/reference_guide.html"><strong aria-hidden="true">24.</strong> bcc Reference Guide</a></li><li class="chapter-item expanded "><a href="../bcc-documents/special_filtering.html"><strong aria-hidden="true">25.</strong> Special Filtering</a></li><li class="chapter-item expanded "><a href="../bcc-documents/tutorial.html"><strong aria-hidden="true">26.</strong> bcc Tutorial</a></li><li class="chapter-item expanded "><a href="../bcc-documents/tutorial_bcc_python_developer.html"><strong aria-hidden="true">27.</strong> bcc Python Developer Tutorial</a></li></ol>
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<h1 id="ebpf-入门实践教程编写-ebpf-程序-memleak-监控内存泄漏"><a class="header" href="#ebpf-入门实践教程编写-ebpf-程序-memleak-监控内存泄漏">eBPF 入门实践教程:编写 eBPF 程序 Memleak 监控内存泄漏</a></h1>
<h2 id="背景"><a class="header" href="#背景">背景</a></h2>
<p>内存泄漏对于一个程序而言是一个很严重的问题。倘若放任一个存在内存泄漏的程序运行,久而久之
系统的内存会慢慢被耗尽,导致程序运行速度显著下降。为了避免这一情况,<code>memleak</code>工具被提出。
它可以跟踪并匹配内存分配和释放的请求,并且打印出已经被分配资源而又尚未释放的堆栈信息。</p>
<h2 id="实现原理"><a class="header" href="#实现原理">实现原理</a></h2>
<p><code>memleak</code> 的实现逻辑非常直观。它在我们常用的动态分配内存的函数接口路径上挂载了ebpf程序
同时在free上也挂载了ebpf程序。在调用分配内存相关函数时<code>memleak</code> 会记录调用者的pid分配得到
内存的地址分配得到的内存大小等基本数据。在free之后<code>memeleak</code>则会去map中删除记录的对应的分配
信息。对于用户态常用的分配函数 <code>malloc</code>, <code>calloc</code> 等,<code>memleak</code>使用了 uporbe 技术实现挂载,对于
内核态的函数,比如 <code>kmalloc</code> 等,<code>memleak</code> 则使用了现有的 tracepoint 来实现。</p>
<h2 id="编写-ebpf-程序"><a class="header" href="#编写-ebpf-程序">编写 eBPF 程序</a></h2>
<p>TODO</p>
<h2 id="编译运行"><a class="header" href="#编译运行">编译运行</a></h2>
<p>TODO</p>
<h2 id="总结"><a class="header" href="#总结">总结</a></h2>
<p>TODO</p>
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