The workflow runs on-demand by commenting `/benchmark` on any pull
request. It runs a few iterations of both the base branch and the PR and
posts the results back to the pull request as a comment. Additionally,
detailed plots are available as images in the workflow artifacts.
Unfortunately GitHub doesn't have a way for actions to upload images in
comments.

At the moment the workflow runs two benchmarks, one at a 10k population
size and 10k time steps, and second one at 1M population size and 1k
time steps.

The workflow currently takes on the order of 1 hour to run. We can
easily tweak the set of benchmarks in the future if we want to run more
scenarios, or conversly if we want to reduce the total time.

There is no long-term tracking of benchmark results yet. Doing so is
tricky as the performance of the underlying CI is unlikely to be stable
long-term.

It was merged into touchstone upstream.

I'm getting issues with 24.04 where pak installs some system packages
with apt-get, some system services are upgraded and restarted and the CI
runner is canceled. Not sure what the reason is, but 22.04 doesn't have
this problem.