Developing Rally

Prerequisites

Please ensure that the following packages are installed before installing Rally in development mode:

  • Python 3.4 or better available as python3 on the path (verify with: python3 --version)
  • pip3 available on the path (verify with pip3 --version)
  • JDK 8 or 9
  • git 1.9 or better
  • Gradle 3.3 or better

Please 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
./rally

If you get errors during installation, it is probably due to the installation of psutil which we use to gather system metrics like CPU utilization. Please check the installation instructions of psutil in this case. Keep in mind that Rally is based on Python 3 and you need to install the Python 3 header files instead of the Python 2 header files on Linux.

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

Before we can run our first benchmark, we have to configure Rally. Just invoke ./rally configure and Rally will automatically detect that its configuration file is missing and prompt you for some values and write them to ~/.rally/rally.ini. After you’ve configured Rally, it will exit.

For more information see 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

First of all, please read the contributors guide.

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