## Problem
Would be nice to have a bit more info on cold start metrics.
## Summary of changes
* Change connect compute latency to include `cold_start_info`.
* Update `ColdStartInfo` to include HttpPoolHit and WarmCached.
* Several changes to make more use of interned strings
## Problem
https://github.com/neondatabase/cloud/issues/9642
## Summary of changes
1. Make `EndpointRateLimiter` generic, renamed as `BucketRateLimiter`
2. Add support for claiming multiple tokens at once
3. Add `AuthRateLimiter` alias.
4. Check `(Endpoint, IP)` pair during authentication, weighted by how
many hashes proxy would be doing.
TODO: handle ipv6 subnets. will do this in a separate PR.
Nightly has added a bunch of compiler and linter warnings. There is also
two dependencies that fail compilation on latest nightly due to using
the old `stdsimd` feature name. This PR fixes them.
## Problem
Running some memory profiling with high concurrent request rate shows
seemingly some memory fragmentation.
## Summary of changes
Eventually, we will want to separate global memory (caches) from local
memory (per connection handshake and per passthrough).
Using a string interner for project info cache helps reduce some of the
fragmentation of the global cache by having a single heap dedicated to
project strings, and not scattering them throughout all a requests.
At the same time, the interned key is 4 bytes vs the 24 bytes that
`SmolStr` offers.
Important: we should only store verified strings in the interner because
there's no way to remove them afterwards. Good for caching responses
from console.
## Problem
too many string based IDs. easy to mix up ID types.
## Summary of changes
Add a bunch of `SmolStr` wrappers that provide convenience methods but
are type safe
## Problem
Parsing the IP address at check time is a little wasteful.
## Summary of changes
Parse the IP when we get it from cplane. Adding a `None` variant to
still allow malformed patterns
## Problem
There are a lot of responses with 404 role not found error, which are
not getting cached in proxy.
## Summary of changes
If there was returned an empty secret but with the project_id, store it
in cache.
## Problem
Current cache doesn't support any updates from the cplane.
## Summary of changes
* Added redis notifier listner.
* Added cache which can be invalidated with the notifier. If the
notifier is not available, it's just a normal ttl cache.
* Updated cplane api.
The motivation behind this organization of the data is the following:
* In the Neon data model there are projects. Projects could have
multiple branches and each branch could have more than one endpoint.
* Also there is one special `main` branch.
* Password reset works per branch.
* Allowed IPs are the same for every branch in the project (except,
maybe, the main one).
* The main branch can be changed to the other branch.
* The endpoint can be moved between branches.
Every event described above requires some special processing on the
porxy (or cplane) side.
The idea of invalidating for the project is that whenever one of the
events above is happening with the project, proxy can invalidate all
entries for the entire project.
This approach also requires some additional API change (returning
project_id inside the auth info).
