Speaker
Description
The ATLAS experiment at the LHC at CERN uses a large, distributed trigger and
data acquisition system composed of many computing nodes, networks, and
hardware modules. Its configuration service is used to provide descriptions of
control, monitoring, diagnostic, recovery, dataflow and data quality
configurations, connectivity, and parameters for modules, chips, and channels
of various online systems, detectors, and the whole ATLAS experiment. Those
descriptions have historically been stored in more than one thousand
interconnected XML files, which are updated by various experts many times per
day. Maintaining error-free and consistent sets of such files and providing
reliable and fast access to current and historical configurations is a major
challenge. This paper gives details of the configuration service upgrade on the
modern git version control system backend for LHC Run 3 and its exploitation
experience. It may be interesting for developers using human-readable file
formats, where consistency of the files, performance, access control,
traceability of modifications, and effective archiving are key requirements.
