Axum serve.rs:422 taking 1928 bytes

[Sagebati]

Summary

Hi,

Using tokio-console, we get a warning saying that the axum task is 1928 Bytes, and it's taking a large amount of space. How to reduce the space taken by the serve future. I guess I have to box it somewhere.

axum version

7.9

[yanns]

I saw this warning as well, and I'm personally unsure what we should do about it.

Option 1: we do nothing

• "Big" futures are automatically boxed by tokio (see https://hegdenu.net/posts/how-big-is-your-future/) (but this future is not big enough for that)

Option 2: add box somewhere

• it's known that the rust compiler is not good at optimizing futures created from async/await. But it might get better in the future. If we add a box now, then we'll probably miss the future optimizations.

My personal conclusion: better doing nothing for now. The services I'm running with axum are using much more memory due to json serialization / deserialization.

[Sagebati]

For sure it's a difficult problem, I'll trust the tokio team & rust compiler and do nothing. Thanks for your time.

[yanns]

For the full context: I'm not an expert in this domain. Don't feel shy providing more options, or more data from some possible production issues if you have any.

[lherman-cs]

I'm experiencing this issue too. @yanns @Sagebati do we have an upstream issue link somewhere? Is this related to async-trait removal?

[Sagebati]

There is no upstream issue as I know. I'm using axum 7.9 so it's not related to the 0.8 async-trait removal.