The coordinated usage pattern

The ESM builds as before a complete distribution of the software needed and supplies a well crafted discovery script. In addition the ESMs communicate to the site managers the packages that they need. The site managers will then install packages locally.

Especially for sites that support only a small number of VOs this can result in a situation where almost the complete software is locally available. Which for either mode of operation comes close to the optimum in terms if efficiency.