Merge pull request #151 from rust-lang/docs-rustc-perf-specify-versio…

…ns-to-keep-up-to-date

docs(rustc-perf): specify versions to keep up to date

service-catalog/rustc-perf/README.md

@@ -13,9 +13,22 @@ It also uses the `shared` db of [rds-databases] and the `rustc-perf` S3 bucket.
 
 The collector (the machine that runs the benchmarks) is a dedicated physical server running at [Hetzner].
 
+## Versions
+
+These are the versions we need to keep up-to-date:
+
+- Node and Ubuntu version specified in the [Dockerfile]
+- Dependencies of [Cargo.lock] and [package-lock.json]
+- Postgres version of the `shared` database
+- GitHub Actions versions in [workflows]
+
 [Rustc perf]: https://perf.rust-lang.org/
 [rustc-perf]: https://github.com/rust-lang/rustc-perf
 [terraform/rustc-perf]: https://github.com/rust-lang/simpleinfra/tree/master/terraform/rustc-perf
 [wg-compiler-performance]: https://github.com/orgs/rust-lang/teams/wg-compiler-performance
 [rds-databases]: https://github.com/rust-lang/simpleinfra/tree/master/terraform/rds-databases
 [Hetzner]: https://www.hetzner.com/
+[Dockerfile]: https://github.com/rust-lang/rustc-perf/blob/master/Dockerfile
+[Cargo.lock]: https://github.com/rust-lang/rustc-perf/blob/master/Cargo.lock
+[package-lock.json]: https://github.com/rust-lang/rustc-perf/blob/master/site/frontend/package-lock.json
+[workflows]: https://github.com/rust-lang/rustc-perf/tree/master/.github/workflows