Hi All, OSC announced its X10 workshop for August. In response, a member of the physics community sent along some pointed questions.
Below, I have included his questions and my attempt at answers. If anyone on this list has anything more concrete to add, I will pass it along. >> >> When I got a previous X10 announcement for OSC, I looked up X10 and had >> trouble believing this was serious -- the most obvious points being >> to me: >> >> 1. what is java doing there (save as a potential guide for suggesting >> new programmers avoid some cmds in C++, at least at the start)? > > Java was selected as the base language for X10, but X10 is not java. It > provides native arrays for scientific computing that are similar to C, for > example. > >> >> 2. Why is there no way of incorporating fortran code? >> > > While X10 is based on Java, it need not be run in the java virtual machine. > It can be compiled. IBM has built a compiler and linking with externally > compiled libraries is supported. I will check on the FORTRAN > compatibilities. > >> Then I called around and discovered no one who believed this was >> serious. >> >> Who with computer intensive routines that worked and >> had survived numerous ports is going to rewrite them, >> save to improve parallelization. >> > > Computer architectures for HPC are changing to clusters of combined > multicore/manycore devices (now CPUs + GPUs, more integrated versions later). > In order to truly take advantage of these architectures, I believe (and this > is editorializing, but hey, it's an email :-) applications will have to > express multilevel parallelism, explicitly manage multiple memory spaces and > overlap computation with communication. The driving motivation behind the > X10 language is to make this kind of programming easier. > >> Who with a working code using all of C++ that works on >> large scale parallel machines is going to rewrite in a >> limited version of C++? > > This is a serious issue. Anytime a new language is proposed, the question of > supporting legacy codes arises (and rightly so). Adoption of a language is > measured in decades. If the X10 community gets more things right than they > get wrong and users find it acceptable, then it might catch on. But, it will > take time. > >> Is it really true that blue waters will only handles X10? > > Absolutely not. From everything I have seen, Blue Waters will support > fortran, C, C++, MPI, OpenMP, etc. And, X10 runs on more than just Blue > Waters. I am compiling and running X10 example on my mac and on Glenn, OSC's > cluster. > >> Is there a >> compiler that had passed many of the standard tests on a variety >> of program types? >> > > Well, there is a compiler. I don't quite know how to answer the "many of the > standard tests" question - do you have specifics? > >> If you were only the messenger, please send this to someone who can >> answer these concerns. >> >> This is a not a rush question, but it is a serious one. > > I completely understand the seriousness of the question! I am always > interested in helping people write better parallel code. I will let you know > when I get more specifics. > > Regards, > Dave Thanks, Dave --- David E. Hudak, Ph.D. dhu...@osc.edu Program Director, HPC Engineering Ohio Supercomputer Center http://www.osc.edu ------------------------------------------------------------------------------ ThinkGeek and WIRED's GeekDad team up for the Ultimate GeekDad Father's Day Giveaway. ONE MASSIVE PRIZE to the lucky parental unit. See the prize list and enter to win: http://p.sf.net/sfu/thinkgeek-promo _______________________________________________ X10-users mailing list X10-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/x10-users
