Putting It All Together：Experience and Challenges at the DELPHI off—line Processing Farm

After over 10 years of existence,DELPHI off-line software counts altogether over 1500k lines.Being written by multitude of authorsk,many of them having already left,it is very incoherent and extremely difficult to maintain:it is written in Fortran,it relies on obsolete tools and it has to run in a distributed multi-os computing environment.Still.as the analysis of LEP data will continue during the next 5-6 years,this code will have to be used and be ported to yet another platforms.In order to ensure high efficiency in use of our resources,we have developed several tools which hide from the user most of the intricaices of the operating system,batch system and data access.These tools are well integrated and easy to maintain.As the problems are quite typical for the High Energy Physics software,we believe that the ideas we have implemented can be useful also for the next generation of experiments.