Troubleshoot the high memory consumption of Go program

Download test code

go get You can get the test program , Pay attention to add -d Avoid automatic installation after downloading .

Github

go get -d github.com/wolfogre/go-pprof-practice
cd $GOPATH/src/github.com/wolfogre/go-pprof-practice

If go get Can't download , Sure git clone download

git clone https://github.com/wolfogre/go-pprof-practice

Compile the code

And then run

go mod init
go mod tidy

Last run

go build
./go-pprof-practice

function pprof command

go tool pprof http://localhost:6060/debug/pprof/heap

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list command

You can see that the problem is github.com/wolfogre/go-pprof-practice/animal/muridae/mouse.(*Mouse).Steal, The function looks like this ：

func (m *Mouse) Steal() {
 log.Println(m.Name(), "steal")
 max := constant.Gi
 for len(m.buffer) * constant.Mi < max {
  m.buffer = append(m.buffer, [constant.Mi]byte{})
 }
}

You can see , There's a cycle going all the way to m.buffer The additional length is 1 MiB Array of , Until the total capacity reaches 1 GiB until , And never release these memory , No wonder there is such a high memory footprint . Use web To see a graphical presentation , It can be confirmed again that the problem is really here ：

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Reference material

• https://blog.wolfogre.com/posts/go-ppof-practice/#%E6%8E%92%E6%9F%A5-cpu-%E5%8D%A0%E7%94%A8%E8%BF%87%E9%AB%98