🔍
Go binary size SVG treemap
Make treemap breakdown of Go executable binary
$ go install github.com/nikolaydubina/go-binsize-treemap@latest
$ go tool nm -size
| go-binsize-treemap > binsize.svg
Disclaimer
Should you be worried about executable binary size? In 2022, few seconds of cat videos or even a single image is tens of MBs. Transferring them over network is not a big deal either. So, probably, you should not worry too much about it. However, this tool can still be useful in couple of cases.
- You are studying compiler.
- You are investigating what 3rd party dependencies are getting included in binary.
- You are checking much data is getting embedded.
- You are estimating how much code is getting included by packages.
- You are researching which symbols included.
- You are doing
cgo. - You are doing treemap visualizations.
I build this in my spare time as another usecase for Go treemap tooling that I built before. Enjoy! Submit issues or PRs!
Examples
github.com/gohugoio/hugo
62MB, this famous example of large Go project
github.com/cockroachdb/cockroach
71MB, this famous db is building with C++
github.com/goccy/go-graphviz
6.5MB, this project has CGO and builds with lots of graphviz code in C
Knowledge Base
What is
go.itab?
This is interface related code. Refer to this article by Russ Cox.
What is
runtime.pclntab? And why it is so big?
As investigated Cockroach team, it is Go runtime structure for traces (reference). Past discussions in GitHub thread on why it is big and what to do about it (well, nothing).
Known Issues and TODOs
- Size slightly mismatches actual binary size. Including unknown does not help.
- C++
- identify go:embed
- color by type + increasing luminance (sys; user; c++; go:embed; etc.)
- color by symbol type
- heat by ????
Related Work
- https://github.com/knz/go-binsize-viz — this was an inspiration for current tool. However, instead of Python and D3 and Javascript, this tool is using single stack purely in Go and has test coverage. Arguably, the downside it is not interactive.
- https://github.com/jondot/goweight — looks like it was working in the beginning, but as of 2022-01-22 it does not work anymore for me and there were reports dating back to 2020-01-23 for it to be not accurate.
Reference
- https://github.com/knz/go-binsize-viz
- https://github.com/jondot/goweight
- https://github.com/nikolaydubina/treemap
- https://github.com/nikolaydubina/go-cover-treemap
- https://github.com/golang/go/blob/master/src/cmd/nm/doc.go
- https://linux.die.net/man/1/c++filt
- https://github.com/goccy/go-graphviz
- https://research.swtch.com/interfaces
Appendix A: Strange Output / C++ / CGO
You many need to demungle symtab file first. Install c++flit. Then process symtab first. Note, c++ support is work in progress.
$ go tool nm -size
| c++filt | go-binsize-treemap > binsize.svg
Appendix B: Large dimensions and lots of details
If you set dimensions very large you can see lots of details and navigate map.
4096x4096 is recommended
... but you can go much higher 
Appendix C: Small dimensions and informative preview
You can generate small preview of project that fits for embedding in README for example.
1024x256 is recommended
