O2openaccess

Repository for ALICE open access software

ALICE software documentation

https://aliceo2group.github.io/analysis-framework/
https://indico.cern.ch/event/1574136/timetable/

Structure of repository

• Root of repository have the enable, enable_local and build_cmd scripts used for
  loading O2Physics environment and build the example analysis from src/ directory (see below)

• cmake/ and src/ contain the example analysis task

  • the compilation of this stand-alone analysis task is done by build_cmd command

• analysis/ directory contain the files required to run an example analysis

  • see the Analysis info

• See Container info for information on the tools to build an cvmfs enabled EL9 container

• cvmfs/ have cvmfs2go script to be able to use cvmfs within a container (for hosts where cvmfs is not available)

  • taken from https://github.com/adriansev/cvmfs2go
  • see the cvmfs/README.md for more information

• upload/ Is dedicated to ALICE OpenData operators for uploading data to OpenData EOS storage

  • see Uploading data to CERN OpenData

Requirements

• Any Linux (x86_64 architecture) with container capabilities
• apptainer or singularity installed for usage of cvmfs2go + el9cvmfs container

Environment setup/loading

enable/enable_local are to be sourced to load the O2Physics environment in current shell (N.B.!!!)

• take as a 1st argument a tag name of O2Physics installation
  • For usage of cvmfs distributed O2Physics: source enable <optional O2Physics tag>
  • For usage of a local compiled O2Physics: source enable_local <optional O2Physics local build tag>

There are a few of steering env vars:

• O2OPENACCESS_SW_TAG_LOCAL : tag name to be used for O2Physics dependency(local installed)
  • It has a default of: latest-o2physics-o2
• O2OPENACCESS_SW_TAG_CVMFS : tag name to be used for O2Physics dependency(cvmfs based)
  • It has a default of: daily-20260126-0000-1

Another way to specify the software tag to be used is to provide it as an argument like:

• ./enable daily-20260126-0000-1
• ./enable_local latest-o2physics-o2

Building

Within the repository, use ./build_cmd for task compilation It has the following arguments:

• debug : enable very verbose debug options for cmake
• build_cmd take as argument [local] tag_name
  • use local to specify that the tag_name is of a local O2Physics installation and as such enable_local script will be used

N.B. clang is a requirement for building O2Physics software !!!

Running analysis

See details in analysis directory
Use the provided ./run_analysis example to run analysis in an already loaded environment

To find help on options use: o2-analysistutorial-flow-analysis --help

or for more comprehensive help o2-analysistutorial-flow-analysis --help full

For running analysis in singularity containen make use of cvmfs2go script from cvmfs directory.

If required, on the subject of CCDB objects caching see CCDB caching information