We were recently asked to install a new piece of scientific software on one of the compute clusters. This software relies on a number of other pieces of software which we didn’t already have installed. And those in turn have dependencies. You can see where this is going. By the end of the process we’d got a whole new compiler, MPI library, and maths libraries to go with the new software. All of these things will be useful in the future but took quite some time to build and hook together.
Which brings me onto a quick plug for the University Computing Service’s excellent course on building software on Linux. The course notes are at http://www.ucs.cam.ac.uk/docs/course-notes/unix-courses/Building and the course itself is next running in March 2013. Highly recommended for anyone who needs to build scientific software on Linux!