CERN Accelerating science

CMS Note
Report number	CMS-CR-2009-075
Title	Validation of Software Releases for CMS
Author(s)	Gutsche, Oliver (Fermilab)
Collaboration	for the CMS Collaboration
Submitted to	17th International Conference on Computing in High Energy and Nuclear Physics, Prague, Czech Republic, 21 - 27 Mar 2009
Submitted by	14 May 2009
Subject category	Detectors and Experimental Techniques
Accelerator/Facility, Experiment	CERN LHC ; CMS
Free keywords	SOFTWARE ; COMPUTING
Abstract	The CMS software stack currently consists of more than 2 Million lines of code developed by over 250 authors with a new version being released every week. CMS has setup a validation process for quality assurance which enables the developers to compare the performance of a release to previous releases and references. The validation process provides the developers with reconstructed datasets of real data and MC samples. The samples span the whole range of detector effects and important physics signatures to benchmark the performance of the software. They are used to investigate interdependency effects of all CMS software components and to find and fix bugs. The release validation process described here is an integral part of CMS software development and contributes significantly to ensure stable production and analysis. It represents a sizable contribution to the overall MC production of CMS. Its success emphasizes the importance of a streamlined release validation process for projects with a large code basis and significant number of developers and can function as a model for future projects.
Copyright/License	Preprint: (License: CC-BY-4.0)