WLCG Accounting is an important task to monitor the available and used resources of the LHC computation grid. Accountable resources involve EOS storage space for the experiments.
In order to support this task force from the EOS side, EOS has introduced a new accounting interface (see accounting CLI command) to make the necessary information easily available. The accounting information consist of the quota nodes statistics and other custom, user specified data which can be provided as specific extended attributes. The output of the command is JSON text standardized for this purpose. It also supports a wide range of caching possibilities.
EOS has introduced a new feature, called “smart files” to make this new feature easy to access. The purpose of this is to be able create special (empty) files in the EOS namespace which execute specified EOS command instead upon reading them. So the accounting command can be configured as a “smart file” and the report can be easily accessed through the REST interface.