Hi David, On Monday, 15 June 2015 00:30:40 UTC+2, David P. Sanders wrote: > > Out of interest, does your code use arrays (for positions if the particles > etc?) If so, does it use standard Julia arrays? > > David
Yes, I use standard Julia arrays. To get Fortran-like performance I have to code carefully to ensure sequential memory access and to avoid garbage collection. My main data structure is a 7xN matrix, where N is the number of particles and each column contains everything I need for one particle (x,y,z position, u,v,w velocity, mass). When I rewrote my program to avoid memory allocation and garbage collection I saw a 35% speed improvement. This optimized version is about 40% faster than the unoptimized Fortran version. But if I add aggressive optimization flags, the Fortran program becomes 40% faster. In the end, Julia seems to be competitive with Fortran. Cheers, Daniel.
