What is LAVA?

LAVA is the Linaro Automation and Validation Architecture.

LAVA is a continuous integration system for deploying operating systems onto physical and virtual hardware for running tests. Tests can be simple boot testing, bootloader testing and system level testing, although extra hardware may be required for some system tests. Results are tracked over time and data can be exported for further analysis.

LAVA is a collection of participating components in an evolving architecture. LAVA aims to make systematic, automatic and manual quality control more approachable for projects of all sizes.

LAVA is designed for validation during development - testing whether the code that engineers are producing “works”, in whatever sense that means. Depending on context, this could be many things, for example:

  • testing whether changes in the Linux kernel compile and boot
  • testing whether the code produced by gcc is smaller or faster
  • testing whether a kernel scheduler change reduces power consumption for a certain workload
  • etc.

LAVA is good for automated validation. LAVA tests the Linux kernel on a range of supported boards every day. LAVA tests proposed android changes in gerrit before they are landed, and does the same for other projects like gcc. Linaro runs a central validation lab in Cambridge, containing racks full of computers supplied by Linaro members and the necessary infrastucture to control them (servers, serial console servers, network switches etc.)

LAVA is good for providing developers with the ability to run customised test on a variety of different types of hardware, some of which may be difficult to obtain or integrate. Although LAVA has support for emulation (based on QEMU), LAVA is best at providing test support for real hardware devices.

LAVA is principally aimed at testing changes made by developers across multiple hardware platforms to aid portability and encourage multi-platform development. Systems which are already platform independent or which have been optimised for production may not necessarily be able to be tested in LAVA or may provide no overall gain.

Note

This overview document explains LAVA using http://validation.linaro.org/ which is the official production instance of LAVA hosted by Linaro. Where examples reference validation.linaro.org, replace with the fully qualified domain name of your LAVA instance.

What is LAVA not?

  • LAVA is not a set of tests - it is infrastructure to enable users to run their own tests. LAVA concentrates on providing a range of deployment methods and a range of boot methods. Once the login is complete, the test consists of whatever scripts the test writer chooses to execute in that environment.
  • LAVA is not a test lab - it is the software that can used in a test lab to control test devices.
  • LAVA is not a complete CI system - it is software that can form part of a CI loop. LAVA supports data extraction to make it easier to produce a frontend which is directly relevant to particular groups of developers.
  • LAVA is not a build farm - other tools need to be used to prepare binaries which can be passed to the device using LAVA.
  • LAVA is not a production test environment for hardware - LAVA is focused on developers and may require changes to the device or the software to enable automation. These changes are often unsuitable for production units. LAVA also expects that most devices will remain available for repeated testing rather than testing the software with a changing set of hardware.

See also

Continuous Integration which covers how LAVA relates to continuous integration (CI) and covers the consequences of what LAVA can and cannot do with particular emphasis on how automation itself can block some forms of testing.