This upgrades the `proxy/` crate as well as the forked libraries in
`libs/proxy/` to edition 2024.
Also reformats the imports of those forked libraries via:
```
cargo +nightly fmt -p proxy -p postgres-protocol2 -p postgres-types2 -p tokio-postgres2 -- -l --config imports_granularity=Module,group_imports=StdExternalCrate,reorder_imports=true
```
It can be read commit-by-commit: the first commit has no formatting
changes, only changes to accomodate the new edition.
Part of #10918
Follow up to #9803
See https://github.com/neondatabase/cloud/issues/14378
In collaboration with @cloneable and @awarus, we sifted through logs and
simply demoted some logs to debug. This is not at all finished and there
are more logs to review, but we ran out of time in the session we
organised. In any slightly more nuanced cases, we didn't touch the log,
instead leaving a TODO comment.
I've also slightly refactored the sql-over-http body read/length reject
code. I can split that into a separate PR. It just felt natural after I
switched to `read_body_with_limit` as we discussed during the meet.
## Problem
There was a bug in dynamic rate limiter, which exhausted CPU in proxy
and proxy wasn't able to accept any connections.
## Summary of changes
1. `if self.available > 1` -> `if self.available >= 1`
2. remove `timeout_at` to use just timeout
3. remove potential infinite loops which can exhaust CPUs.
## Problem
Computes that are healthy can manage many connection attempts at a time.
Unhealthy computes cannot. We initially handled this with a fixed
concurrency limit, but it seems this inhibits pgbench.
## Summary of changes
Support AIMD for connect_to_compute lock to allow varying the
concurrency limit based on compute health
## Problem
There is an unused dead code.
## Summary of changes
Let's remove it. In case we would need it in the future, we can always
return it back.
Also removed cli arguments. They shouldn't be used by anyone but us.
