Sometimes, it contained real values, sometimes just defaults if the
spec was not received yet. Make the state more clear by making it an
Option instead.
One consequence is that if some of the required settings like
neon.tenant_id are missing from the spec file sent to the /configure
endpoint, it is spotted earlier and you get an immediate HTTP error
response. Not that it matters very much, but it's nicer nevertheless.
This is in preparation of using compute_ctl to launch postgres nodes
in the neon_local control plane. And seems like a good idea to
separate the public interfaces anyway.
One non-mechanical change here is that the 'metrics' field is moved
under the Mutex, instead of using atomics. We were not using atomics
for performance but for convenience here, and it seems more clear to
not use atomics in the model for the HTTP response type.
This commit adds an option to start compute without spec and then pass
it a valid spec via `POST /configure` API endpoint. This is a main
prerequisite for maintaining the pool of compute nodes in the
control-plane.
For example:
1. Start compute with
```shell
cargo run --bin compute_ctl -- -i no-compute \
-p http://localhost:9095 \
-D compute_pgdata \
-C "postgresql://cloud_admin@127.0.0.1:5434/postgres" \
-b ./pg_install/v15/bin/postgres
```
2. Configure it with
```shell
curl -d "{\"spec\": $(cat ./compute-spec.json)}" http://localhost:3080/configure
```
Internally, it's implemented using a `Condvar` + `Mutex`. Compute spec
is moved under Mutex, as it's now could be updated in the http handler.
Also `RwLock` was replaced with `Mutex` because the latter works well
with `Condvar`.
First part of the neondatabase/cloud#4433
After enabling autoscaling, we faced the issue that customers are not
able to get the number of CPUs they use at this moment. Therefore I've
added these two options:
1. Postgresql function to allow customers to call it whenever they want
2. `compute_ctl` endpoint to show these number in console
This commit adds a basic HTTP API endpoint that allows scraping the
`pg_stat_statements` data and getting a list of slow queries. New
insights like cache hit rate and so on could be added later.
Extension `pg_stat_statements` is checked / created only if compute
tries to load the corresponding shared library. The latter is configured
by control-plane and currently covered with feature flag.
Co-authored by Eduard Dyckman (bird.duskpoet@gmail.com)
Refactors Compute::prepare_and_run. It's split into subroutines
differently, to make it easier to attach tracing spans to the
different stages. The high-level logic for waiting for Postgres to
exit is moved to the caller.
Replace 'env_logger' with 'tracing', and add `#instrument` directives
to different stages fo the startup process. This is a fairly
mechanical change, except for the changes in 'spec.rs'. 'spec.rs'
contained some complicated formatting, where parts of log messages
were printed directly to stdout with `print`s. That was a bit messed
up because the log normally goes to stderr, but those lines were
printed to stdout. In our docker images, stderr and stdout both go to
the same place so you wouldn't notice, but I don't think it was
intentional.
This changes the log format to the default
'tracing_subscriber::format' format. It's different from the Postgres
log format, however, and because both compute_tools and Postgres print
to the same log, it's now a mix of two different formats. I'm not
sure how the Grafana log parsing pipeline can handle that. If it's a
problem, we can build custom formatter to change the compute_tools log
format to be the same as Postgres's, like it was before this commit,
or we can change the Postgres log format to match tracing_formatter's,
or we can start printing compute_tool's log output to a different
destination than Postgres
+ neondatabase/cloud#1103
This adds a couple of control endpoints to simplify compute state
discovery for control-plane. For example, now we may figure out
that Postgres wasn't able to start or basebackup failed within
seconds instead of just blindly polling the compute readiness
for a minute or two.
Also we now expose startup metrics (time of the each step: basebackup,
sync safekeepers, config, total). Console grabs them after each
successful start and report as histogram to prometheus and grafana.
OpenAPI spec is added and up-tp date, but is not currently used in the
console yet.
