No. 38 (00129) Family name : Rademakers Given name : Fons Affiliation : CERN Abbreviation : E-mail address : Fons.Rademakers@cern.ch Title : Parallel Interactive Analysis on tsis on the GRID using PROOF and CONDORe GRID using PROOF and CONDOR Authors : Maarten Ballintijn, Fons Rademakers Abstract : The Parallel ROOT Facility, PROOF, enables a physicist to analyze and understand much larger data sets on a shorter time scale. It makes use of the inherent parallelism in event data and implements an architecture that optimizes I/O and CPU utilization in heterogeneous clusters with distributed storage. The system provides transparent and interactive access to gigabytes today. Being part of the ROOT framework PROOF inherits the benefits of a performant object storage system and a wealth of statistical and visualization tools. In this paper we describe how PROOF uses the new CONDOR Computing On Demand (COD) features to get high priority access to nodes in a cluster. This is the first step to fully Grid enabling the PROOF system.