[reeses]

Fortran (especially ancient, wheezy Fortran) lent itself to supervised automatic parallelization because of its lack of dynamic arrays. It was "easy" to vectorize code at compile time when you had so much information about the runtime expectations.

We can do some of this now in most languages with hot-spot profiling, basic block analysis, selective inlining, and other innovations. However, you really can't beat low-level languages that explicitly "hint" at their execution paths.

By the same token, Cray's applications were...so...slow if you were foolish enough to run them on the expensive hardware and not the FEPs.