Simulation Systems Glossary

Please suggest new entries to the Simulation Systems and Deployment Team

Closed Release:

A release cycle where the only accepted changes to main relate to a particular piece of work, either technical or scientific. A release can also be partially closed, with only one area of a code base locked down in this way, and the rest free for changes.

Code Review Deadline:

The date by which all pull requests aiming to be included in a release have been moved into code review.

Code Review:

A technical review of the changes involved in the pull request, including checks that code standards have been upheld and that the working practices have been followed. These reviews are generally completed by a member of the Simulation IT Team. Once a review has been approved the Code Systems Reviewer is then responsible for committing the change to the main.

Development Window:

The period of time between the release of one software version and the code review deadline for the following release in which new developments are accepted for review.

Known Good Output (KGO):

In order to verify that the model output hasn’t been modified by a set of changes the test suite contains a stored set of output as a reference. This is known as the KGO and changes that alter this require special treatment. For more information see Known Good Output (KGO).

Head of Main:

The most recent commit hash on main. Branches are taken from here when the work being done has to be built on top of changes already made since the last release.

Linked Pull Request (Linked PR):

Work that spans two or more repositories, requiring pull requests that should be treated together and committed as a group.

Overarching Issue:

Where a piece of work has been split into multiple sections an overarching issue can be used to track this work. It should be closed when the whole arc has been completed. GitHub also allows subissues which can be created from the overarching issue.

Regression:

A set of tests that prove that a set of code changes have not degraded the model output. Comparisons are made between the results produced and the Known Good Output.

SciTech Review:

A science or technical review, completed by someone who is familiar with the area being changed. The aim of this review is to confirm that the changes made do what they say they should, and that the method used was appropriate.

Simulation Systems and Deployment Team:

The team responsible for the oversight of these working practices. For more information see Simulation IT.

Simulation Systems Governance Group:

The governing body that oversees the work of the Simulation Systems and Deployment Team.

Version:

Each release of the codebase is completed by tagging the stable branch with a version number. This version should be used for creating code branches from and will also be used by the parallel suite teams as a starting point for creating the next operational suite.