Dont show underlying data structure in flamegraph when using the example

[zuston]

Thanks for your great work!

I used this project example to run and try to show the memory profile in flamegrph. But I haven't seen the underlying data structure that used the too much memory in the flamegraph, that only shows the binary name, like this:

.

And I run the exmaple binary, and then use the following command to fetch the heap sample.

./rust-jemalloc-pprof-example

curl http://localhost:3000/debug/pprof/heap >  heap.pb.gz
go tool pprof -http="0.0.0.0:8081" heap.pb.gz

[zuston]

cc @flavio @umanwizard @lucab