## Problem
1. Hard to correlate startup parameters with the endpoint that provided
them.
2. Some configurations are not needed in the `ProxyConfig` struct.
## Summary of changes
Because of some borrow checker fun, I needed to switch to an
interior-mutability implementation of our `RequestMonitoring` context
system. Using https://docs.rs/try-lock/latest/try_lock/ as a cheap lock
for such a use-case (needed to be thread safe).
Removed the lock of each startup message, instead just logging only the
startup params in a successful handshake.
Also removed from values from `ProxyConfig` and kept as arguments.
(needed for local-proxy config)
## Problem
The current bucket based rate limiter is not very intuitive and has some
bad failure cases.
## Summary of changes
Switches from fixed interval buckets to leaky bucket impl. A single
bucket per endpoint,
drains over time. Drains by checking the time since the last check, and
draining tokens en-masse. Garbage collection works similar to before, it
drains a shard (1/64th of the set) every 2048 checks, and it only
removes buckets that are empty.
To be compatible with the existing config, I've faffed to make it take
the min and the max rps of each as the sustained rps and the max bucket
size which should be roughly equivalent.
## Problem
If there's a quota error, it makes sense to cache it for a short window
of time. Many clients do not handle database connection errors
gracefully, so just spam retry 🤡
## Summary of changes
Updates the node_info cache to support storing console errors. Store
console errors if they cannot be retried (using our own heuristic.
should only trigger for quota exceeded errors).
## Problem
1. Proxy is retrying errors from cplane that shouldn't be retried
2. ~~Proxy is not using the retry_after_ms value~~
## Summary of changes
1. Correct the could_retry impl for ConsoleError.
2. ~~Update could_retry interface to support returning a fixed wait
duration.~~
## 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
We were rate limiting wake_compute in the wrong place
## Summary of changes
Move wake_compute rate limit to after the permit is acquired. Also makes
a slight refactor on normalize, as it caught my eye
## 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 no global per-ep rate limiter in proxy.
## Summary of changes
* Return global per-ep rate limiter back.
* Rename weak compute rate limiter (the cli flags were not used
anywhere, so it's safe to rename).
## Problem
If a permit cannot be acquired to connect to compute, the cache is
invalidated. This had the observed affect of sending more traffic to
ProxyWakeCompute on cplane.
## Summary of changes
Make sure that permit acquire failures are marked as "should not
invalidate cache".
## Problem
Too many connect_compute attempts can overwhelm postgres, getting the
connections stuck.
## Summary of changes
Limit number of connection attempts that can happen at a given time.
## Problem
Actually read redis events.
## Summary of changes
This is revert of https://github.com/neondatabase/neon/pull/7350 +
fixes.
* Fixed events parsing
* Added timeout after connection failure
* Separated regional and global redis clients.
## Problem
My benchmarks show that prometheus is not very good.
https://github.com/conradludgate/measured
We're already using it in storage_controller and it seems to be working
well.
## Summary of changes
Replace prometheus with my new measured crate in proxy only.
Apologies for the large diff. I tried to keep it as minimal as I could.
The label types add a bit of boiler plate (but reduce the chance we
mistype the labels), and some of our custom metrics like CounterPair and
HLL needed to be rewritten.
## Problem
Proxy doesn't know about existing endpoints.
## Summary of changes
* Added caching of all available endpoints.
* On the high load, use it before going to cplane.
* Report metrics for the outcome.
* For rate limiter and credentials caching don't distinguish between
`-pooled` and not
TODOs:
* Make metrics more meaningful
* Consider integrating it with the endpoint rate limiter
* Test it together with cplane in preview
## 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
I noticed code coverage for auth_quirks was pretty bare
## Summary of changes
Adds 3 happy path unit tests for auth_quirks
* scram
* cleartext (websockets)
* cleartext (password hack)
## Problem
Currently cplane communication is a part of the latency monitoring. It
doesn't allow to setup the proper alerting based on proxy latency.
## Summary of changes
Added dimension to exclude cplane latency.
## Problem
* quotes in serialized string
* no status if connection is from local cache
## Summary of changes
* remove quotes
* report warm if connection if from local cache
## Problem
`422 Unprocessable Entity: compute time quota of non-primary branches is
exceeded` being marked as a control plane error.
## Summary of changes
Add the manual checks to make this a user error that should not be
retried.
## Problem
Branch/project and coldStart were not populated to data events.
## Summary of changes
Populate it. Also added logging for the coldstart info.
## Problem
Actually it's good idea to distinguish between cases when it's a cold
start, but we took the compute from the pool
## Summary of changes
Updated to enum.
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
Data team cannot distinguish between cold start and not cold start.
## Summary of changes
Report `is_cold_start` to analytics.
---------
Co-authored-by: Conrad Ludgate <conrad@neon.tech>
## Problem
## Summary of changes
1. Classify further cplane API errors
2. add 'serviceratelimit' and make a few of the timeout errors return
that.
3. a few additional minor changes
## Problem
Not really a problem, just refactoring.
## Summary of changes
Separate authenticate from wake compute.
Do not call wake compute second time if we managed to connect to
postgres or if we got it not from cache.
## Problem
Taking my ideas from https://github.com/neondatabase/neon/pull/6283 and
doing a bit less radical changes. smaller commits.
We currently don't report error classifications in proxy as the current
error handling made it hard to do so.
## Summary of changes
1. Add a `ReportableError` trait that all errors will implement. This
provides the error classification functionality.
2. Handle Client requests a strongly typed error
* this error is a `ReportableError` and is logged appropriately
3. The handle client error only has a few possible error types, to
account for the fact that at this point errors should be returned to the
user.
## Problem
The password check logic for the sql-over-http is a bit non-intuitive.
## Summary of changes
1. Perform scram auth using the same logic as for websocket cleartext
password.
2. Split establish connection logic and connection pool.
3. Parallelize param parsing logic with authentication + wake compute.
4. Limit the total number of clients
## Problem
not really any problem, just some drive-by changes
## Summary of changes
1. move wake compute
2. move json processing
3. move handle_try_wake
4. move test backend to api provider
5. reduce wake-compute concerns
6. remove duplicate wake-compute loop
## Problem
Follow up to #5461
In my memory usage/fragmentation measurements, these metrics came up as
a large source of small allocations. The replacement metric has been in
use for a long time now so I think it's good to finally remove this.
Per-endpoint data is still tracked elsewhere
## Summary of changes
remove the per-client bytes metrics
## Problem
Right now if get_role_secret response wasn't cached (e.g. cache already
reached max size) it will send the second (exactly the same request).
## Summary of changes
Avoid needless request.
## 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
In https://github.com/neondatabase/neon/pull/6283 I did a couple changes
that weren't directly related to the goal of extracting the state
machine, so I'm putting them here
## Summary of changes
- move postgres vs console provider into another enum
- reduce error cases for link auth
- slightly refactor link flow
## Problem
Currently we store in cache even if the project is undefined. That makes
invalidation impossible.
## Summary of changes
Do not store if project id is empty.
## Problem
HTTP connection pool was not respecting the PitR options.
## Summary of changes
1. refactor neon_options a bit to allow easier access to cache_key
2. make HTTP not go through `StartupMessageParams`
3. expose SNI processing to replace what was removed in step 2.
## 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).
## Summary of changes
### RequestMonitoring
We want to add an event stream with information on each request for
easier analysis than what we can do with diagnostic logs alone
(https://github.com/neondatabase/cloud/issues/8807). This
RequestMonitoring will keep a record of the final state of a request. On
drop it will be pushed into a queue to be uploaded.
Because this context is a bag of data, I don't want this information to
impact logic of request handling. I personally think that weakly typed
data (such as all these options) makes for spaghetti code. I will
however allow for this data to impact rate-limiting and blocking of
requests, as this does not _really_ change how a request is handled.
### Parquet
Each `RequestMonitoring` is flushed into a channel where it is converted
into `RequestData`, which is accumulated into parquet files. Each file
will have a certain number of rows per row group, and several row groups
will eventually fill up the file, which we then upload to S3.
We will also upload smaller files if they take too long to construct.
## Problem
control plane should be able to return domain names and not just IP
addresses.
## Summary of changes
1. add regression tests
2. use rsplit to split the port from the back, then trim the ipv6
brackets
