scripts: devcontainer: mount tmpfs on /tmp

This makes tests generally faster, but most importantly, it
significantly deflakes etcd-heavy tests, especially when run with
--runs_per_test=many. Without this, the underlying FS is overlayfs-fuse,
which has very little iops to spare, to the point where etcd servers in
tests will take hundreds of seconds because of iops starvation.

Some cherrypicked figures:

Before:

//metropolis/installer/test:installer                                    PASSED in 30.8s
//metropolis/pkg/event/etcd:etcd_test                                    PASSED in 14.6s

After:
//metropolis/installer/test:installer                                    PASSED in 18.9s
//metropolis/pkg/event/etcd:etcd_test                                    PASSED in 6.1s

This has the downside of possibly eating more RAM on developer machines,
but RAM is cheap. Importantly, our test suite seems to not leak things
into /tmp (other than some leftover empty directories), so RAM usage
within the build container shouldn't balloon.

This is also something that's irrelevant for CI, as CI doesn't use
scripts/{build,destroy}_container.sh.

Change-Id: Iae12f6fdd5b48685f17f1466f2695f3707a0dd62
Reviewed-on: https://review.monogon.dev/c/monogon/+/653
Reviewed-by: Leopold Schabel <leo@nexantic.com>
1 file changed
tree: 1bc2e79cffe7c0d8a2a8b3d1596867493db2b7f5
  1. build/
  2. intellij/
  3. metropolis/
  4. scripts/
  5. third_party/
  6. .bazelignore
  7. .bazelproject
  8. .bazelrc
  9. .git-ignore-revs
  10. .gitignore
  11. BUILD
  12. CODING_STANDARDS.md
  13. go.mod
  14. go.sum
  15. LICENSE
  16. README.md
  17. WORKSPACE
README.md

Monogon Monorepo

This is the main repository containing the source code for the Monogon Project.

This is pre-release software - feel free to look around, and check back later for our first release!

Environment

Our build environment requires a working Podman binary (your distribution should have one).

Usage

Spinning up: scripts/create_container.sh

Spinning down: scripts/destroy_container.sh

Running commands: scripts/run_in_container.sh <...>

Using bazel using a wrapper script: scripts/bin/bazel <...> (add to your local $PATH for convenience)

IntelliJ

This repository is compatible with the IntelliJ Bazel plugin, which enables full autocompletion for external dependencies and generated code. All commands run inside the container, and necessary paths are mapped into the container.

The following steps are necessary:

  • Install Google's Bazel plugin in IntelliJ. On IntelliJ 2020.3 or later, you need to install a beta release of the plugin.

  • Add the absolute path to your ~/.cache/bazel-monogon folder to your idea64.vmoptions (Help → Edit Custom VM Options) and restart IntelliJ:

    -Dbazel.bep.path=/home/leopold/.cache/bazel-monogon

  • Set "Bazel Binary Location" in Other Settings → Bazel Settings to the absolute path of scripts/bin/bazel. This is a wrapper that will execute Bazel inside the container.

  • Use File → Import Bazel project... to create a new project from .bazelproject.

After running the first sync, everything should now resolve in the IDE, including generated code.

Metropolis

Run a single node cluster

Launch the node:

scripts/bin/bazel run //:launch

Run a kubectl command:

scripts/bin/bazel run //metropolis/cli/dbg -- kubectl describe

Run tests:

scripts/bin/bazel test //...