使用Go语言诊断和解决内存泄漏问题-优快云博客

本文链接：https://blog.youkuaiyun.com/yxw2014/article/details/21969421

本文通过示例展示了如何使用Go语言内置的pprof工具来检测内存泄露，重点关注了`reflect.unsafe_NewArray`和`database/sql.convertAssign`函数可能导致的内存占用。内容包括了获取和解析内存剖析报告，以及如何进一步分析内存泄露的位置。

[root@s3 twitter]# go tool pprof http://localhost:6060/debug/pprof/heap --text
Read http://localhost:6060/debug/pprof/symbol
Fetching /pprof/heap profile from localhost:6060 to
/tmp/76z7mNTrzO
Wrote profile to /tmp/76z7mNTrzO
Adjusting heap profiles for 1-in-524288 sampling rate
Total: 47.5 MB
24.5 51.6% 51.6% 24.5 51.6% reflect.unsafe_NewArray
23.0 48.4% 100.0% 23.0 48.4% database/sql.convertAssign
0.0 0.0% 100.0% 23.0 48.4% database/sql.(*Rows).Scan
0.0 0.0% 100.0% 47.5 100.0% github.com/coopernurse/gorp.(*DbMap).Select
0.0 0.0% 100.0% 47.5 100.0% github.com/coopernurse/gorp.hookedselect
0.0 0.0% 100.0% 47.5 100.0% github.com/coopernurse/gorp.rawselect
0.0 0.0% 100.0% 47.5 100.0% main.getTwitterNoParse
0.0 0.0% 100.0% 27.5 57.9% main.main
0.0 0.0% 100.0% 47.5 100.0% main.parseHtml
0.0 0.0% 100.0% 24.5 51.6% reflect.Append
0.0 0.0% 100.0% 24.5 51.6% reflect.MakeSlice
0.0 0.0% 100.0% 24.5 51.6% reflect.grow
0.0 0.0% 100.0% 1.4 2.9% runtime.MProf_Malloc
0.0 0.0% 100.0% 1.4 2.9% runtime.callers
0.0 0.0% 100.0% 25.1 52.8% runtime.gosched0

0.0 0.0% 100.0% 26.8 56.4% runtime.main

[root@s3 twitter]# go tool pprof http://localhost:6060/debug/pprof/heap --text
Read http://localhost:6060/debug/pprof/symbol
Fetching /pprof/heap profile from localhost:6060 to
/tmp/6rfif3xDyB
Wrote profile to /tmp/6rfif3xDyB
Adjusting heap profiles for 1-in-524288 sampling rate
Total: 57.1 MB
30.1 52.7% 52.7% 30.1 52.7% reflect.unsafe_NewArray
27.0 47.3% 100.0% 27.0 47.3% database/sql.convertAssign
0.0 0.0% 100.0% 27.0 47.3% database/sql.(*Rows).Scan
0.0 0.0% 100.0% 57.1 100.0% github.com/coopernurse/gorp.(*DbMap).Select
0.0 0.0% 100.0% 57.1 100.0% github.com/coopernurse/gorp.hookedselect
0.0 0.0% 100.0% 57.1 100.0% github.com/coopernurse/gorp.rawselect
0.0 0.0% 100.0% 57.1 100.0% main.getTwitterNoParse
0.0 0.0% 100.0% 27.5 48.2% main.main
0.0 0.0% 100.0% 57.1 100.0% main.parseHtml
0.0 0.0% 100.0% 30.1 52.7% reflect.Append
0.0 0.0% 100.0% 30.1 52.7% reflect.MakeSlice
0.0 0.0% 100.0% 30.1 52.7% reflect.grow
0.0 0.0% 100.0% 1.4 2.5% runtime.MProf_Malloc
0.0 0.0% 100.0% 1.4 2.5% runtime.callers
0.0 0.0% 100.0% 25.1 44.0% runtime.gosched0
0.0 0.0% 100.0% 26.8 46.9% runtime.main

内存占用在增加！

(pprof) top
Total: 94.1 MB
49.6 52.7% 52.7% 49.6 52.7% reflect.unsafe_NewArray
44.5 47.3% 100.0% 44.5 47.3% database/sql.convertAssign
0.0 0.0% 100.0% 44.5 47.3% database/sql.(*Rows).Scan

生成svg，得安装graphviz ，浏览器打开svg，图很清楚。

yum install graphviz -y