Analyzing goroutine heap allocations (leak)

[Gavra]

Hi,

I have a heap profile that shows that many allocations are generated in a function that runs in a go routine. Unfortunately, I can't see the caller(s) to this function, implying I cannot detect the one holding the reference (and causing the mem leak).

1. Can I extract this information from the heap profile?

2. If not, can I take a heap profile that will gather this info?

3. Why isn't this info available by default? When the go routine is created, the runtime has all necessary context to indicate the trace call and forward it, shouldn't it always be the behavior?

Thanks.

[Jan Mercl]

You can try something like (adjust the args as needed)

$ go test -run nothing -bench . -memprofile mem.out -memprofilerate 1 -benchtime 4s

$ go tool pprof -lines -web -alloc_space *.test mem.out

HTH

[Gavra]

I am not sure I understand. I have the issue reproducing only in production on a running instance...

[Jan Mercl]

On Mon, Feb 24, 2025 at 9:20 AM Gavra <gav...@gmail.com> wrote:

> I am not sure I understand. I have the issue reproducing only in production on a running instance...

Not mentioned in the OP. You can still try to write tests and/or
benchmarks that exhibit the same memory leak and then use them with
the -memprofile facility.