Legacy code in scientific computing
There is very little legacy code in scientific computing, as we write it from scratch on libraries... e.g. solvers etc...
There may be very little legacy code in your branch of scientific computing. However, this is not the case in many others. For example, your average quantum chemistry code contains many million LOC, some of those going all the way into the mists of time.
However, this means little as far as the choice of CPU architecture goes: exactly because it survived for a long time, this code tends to be portable. Given a decent compiler, it will (and does) run on anything you want.
Of course, if the architecture de jour does not have a decent optimizing compiler for the languages in which these codes are written, it will not be used - or it will be used at best as an offload accelerator.
Biting the hand that feeds IT
