Large-scale parallel geophysical algorithms in Java: a feasibility study

Java is often accused of being too slow for serious programming, especially for scientific problem solving. However, we found that for a large-scale geophysical application, Java code compiled with current just-in-time compilers runs slower than Fortran by a factor of at most 4, on both a shared-memory parallel machine (SGI Origin2000) and a distributed-memory parallel machine (IBM SP/2). The moderate slow-down is easily offset by the following advantages: (a) object-oriented Java code is easier to maintain and reuse than Fortran code; (b) Java code is fully portable, even among parallel computers with different memory models. Furthermore, better compiler technology is on the horizon, which will narrow the performance gap even more. © 1998 John Wiley & Sons, Ltd.