Developing Rally#

Prerequisites#

Install the following software packages:

Check the installation guide for detailed installation instructions for these packages.

Rally does not support Windows and is only actively tested on macOS and Linux.

Installation Instructions for Development#

git clone https://github.com/elastic/rally.git
cd rally
make install
source .venv/bin/activate
./rally --help

IDE Setup#

Rally uses automatic code formatters. You can apply them by running make format.

However, consider using editor integrations to do it automatically: you’ll need to configure black and isort.

Also consider running pre-commit install to run lint as part of your git commits.

Automatic Updates#

Rally has a built-in auto-update feature when you install it from sources. By default, it will update from the remote named origin. If you want to auto-update from a different remote, provide --update-from-remote=YOUR_REMOTE_NAME as first parameter.

To work conveniently with Rally, we suggest that you add the Rally project directory to your PATH. In case you use a different remote, you should also define aliases in your shell’s config file, e.g.:

alias rally='rally --update-from-remote=elastic '
alias rallyd='rallyd --update-from-remote=elastic '

Then you can invoke Rally or the Rally daemon as usual and have auto-update still work.

Also note that automatic updates are disabled in the following cases:

  • There are local (uncommitted) changes in the Rally project directory

  • A different branch than master is checked out

  • You have specified --skip-update as the first command line parameter

  • You have specified --offline as a command line parameter for Rally

Configuring Rally#

Rally creates a default configuration automatically on first run. For further configuration, see the configuration help page.

Key Components of Rally#

To get a rough understanding of Rally, it makes sense to get to know its key components:

  • Race Control: is responsible for proper execution of the race. It sets up all components and acts as a high-level controller.

  • Mechanic: can build and prepare a benchmark candidate for the race. It checks out the source, builds Elasticsearch, provisions and starts the cluster.

  • Track: is a concrete benchmarking scenario, e.g. the http_logs benchmark. It defines the data set to use.

  • Challenge: is the specification on what benchmarks should be run and its configuration (e.g. index, then run a search benchmark with 1000 iterations)

  • Car: is a concrete system configuration for a benchmark, e.g. an Elasticsearch single-node cluster with default settings.

  • Driver: drives the race, i.e. it is executing the benchmark according to the track specification.

  • Reporter: A reporter tells us how the race went (currently only after the fact).

There is a dedicated tutorial on how to add new tracks to Rally.

How to contribute code#

See the contributors guide. We strive to be PEP-8 compliant but don’t follow it to the letter.