使用tcmalloc检测内存泄漏

安装

请自行搜索 google-perftools的安装。

使用tcmalloc检测内存泄露

在执行程序的时候，设置tcmalloc内存泄露检测的相关环境变量：

LD_PRELOAD="/usr/lib64/libtcmalloc.so" HEAPCHECK=normal  ./bin/exe

如果该exe中有内存泄露的话，tcmalloc会打印一些相关信息，如果上面命令的输出如下：

Leak check _main_ detected leaks of 1136 bytes in 2 objects
The 2 largest leaks:
Leak of 568 bytes in 1 objects allocated from:
        @ 7fa7f4197dd2 
        @ 7fa7f4198c30 
        @ 7fa7fd11f780 
        @ 7fa7fd15aaf3 
        @ 7fa7fd15189a 
        @ 7fa7fd1519e8 
        @ 7fa7fd151ac5 
        @ 7fa7fd151d9f 
        @ 7fa7fd15afd3 
        @ 7fa7fd1520ed 
        @ 7fa7fd11ea42 
        @ 7fa7f14dfb35 
        @ 7fa7fd11f151 
        @ 0 
Leak of 568 bytes in 1 objects allocated from:
        @ 7fa7f4197dd2 
        @ 7fa7f4198c30 
        @ 7fa7fd12402f 
        @ 7fa7fd15aaf3 
        @ 7fa7fd15189a 
        @ 7fa7fd1519e8 
        @ 7fa7fd151ac5 
        @ 7fa7fd151d9f 
        @ 7fa7fd15afd3 
        @ 7fa7fd1520ed 
        @ 7fa7fd11ea42 
        @ 7fa7f14dfb35 
        @ 7fa7fd11f151 
        @ 0 


If the preceding stack traces are not enough to find the leaks, try running THIS shell command:

pprof ./bin/exe "/tmp/exe.7539._main_-end.heap" --inuse_objects --lines --heapcheck  --edgefraction=1e-10 --nodefraction=1e-10 --gv

If you are still puzzled about why the leaks are there, try rerunning this program with HEAP_CHECK_TEST_POINTER_ALIGNMENT=1 and/or with HEAP_CHECK_MAX_POINTER_OFFSET=-1
If the leak report occurs in a small fraction of runs, try running with TCMALLOC_MAX_FREE_QUEUE_SIZE of few hundred MB or with TCMALLOC_RECLAIM_MEMORY=false, it mi
Exiting with error code (instead of crashing) because of whole-program memory leaks

然后我们按照tcmalloc的提示，执行pprof相关命令查看内存泄露的代码位置：

pprof ./bin/exe "/tmp/exe.7539._main_-end.heap" --inuse_objects --lines --heapcheck  --edgefraction=1e-10 --nodefraction=1e-10 --text

该命令的输出为文本方式表示的。

使用doc输出内存泄露调用关系图

有的时候，内存泄露相关的调用关系比较复杂，这时候最好能生成调用关系图，方便排查内存泄露问题

1. 生成dot文件

pprof ./bin/exe"/tmp/exe.7539._main_-end.heap" --inuse_objects --lines --heapcheck  --edgefraction=1e-10 --nodefraction=1e-10 --dot > exe.dot

2. 生成png格式的图片

dot -Tpng -o ./exe.png ./exe.dot

也可以通过参数调整输出其他格式的可视化结果。