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dibanez

HN member
Joined
Sat, May 02, 2015, 2:31 PM UTC
HN karma
60
Public activity
21 items

About dibanez

C/C++ HPC programmer, finite elements, parallel programming, graphics, geometry.

Recent public activity

  1. comment
    Comment #14435218

    One of the problems with the current peer review system is the ease with which a reviewer can recommend rejecting a manuscript based on personal conflicts of interest (for example,…

  2. comment
    Comment #13907505

    Without belittling the difficulties of rural areas, it seems just as concerning to me that all the lines in this plot are trending upward.

  3. comment
    Comment #13315266

    Its useful to be able to remove safety checks for speed. I have a C++ code where all data is in array objects. Bounds checking is a compile time option, and it makes the overall co…

  4. comment
    Comment #13279066

    In my parent comment are listed compile times from scratch, although there probably exist one or two files that would trigger similarly long rebuilds (included indirectly by most o…

  5. comment
    Comment #13279020

    I did the single file trick for the small library that I control, as a configure option. It definitely does help, 2X speedup in serial compile time typically. however, you lose the…

  6. comment
    Comment #13277519

    As others have mentioned, I've resorted to brute force (parallel compile using 16 physical cores, good SSD, 32GB RAM). I have a 20KLOC library that I wrote myself (very few templat…

  7. comment
    Comment #12881008

    I've been doing this without thinking about it for a while and after reading it from a beginner's perspective It seems like quite a few steps. It is the "right" thing to do though,…

  8. comment
    Comment #12830011

    Seems reasonable. An interesting bit for me was the CITATION file. The lack of citability for software is a recurring annoyance when writing up work that uses that software.

  9. comment
    Comment #12377580

    Muratori's compression-oriented programming and Acton's data-oriented design have really helped me in writing HPC code. Carmack's arguments make sense for apps that have a clear ma…

  10. comment
    Comment #12377561

    I'm 80% "software engineer" and 20% "researcher" and have to play both roles to write supercomputer code (I'm the minority, most peers are more researchers). These issues are impor…

  11. comment
    Comment #12353354

    Yea, I've seen compilers use lea for some integer math in C/C++, because it is handled by a different part of the CPU and so can happen in parallel with other integer math ops.

  12. comment
    Comment #12199224

    Both, and it agrees with your prediction. KNL's cores are each much faster than KNC's cores. A KNC core was over 10X slower than a mainstream CPU core, and a KNL core seems to only…

  13. comment
    Comment #12199025

    As someone who has programmed both Phis and conventional x86 CPUs, I can confirm that the Phi is more sensitive to data traversal order and NUMA effects on which core accesses whic…

  14. comment
    Comment #12199004

    One of the interesting things to keep in mind is that these new Xeon Phi cards can be used as standalone CPUs, not just as PCIe cards like a GPU. This is the "self-hosted mode" the…

  15. comment
    Comment #11937428

    Its essentially a matter of realistic benchmark acceptance. Right now machines are compared by how well they run this benchmark called LINPACK, which has been criticized for being …

  16. comment
    Comment #11827460

    It may be that mobile graphics gets by fine with FP32 or less, but I worry that if FP64 gets sidelined then none of the effort going into this hardware today will benefit applicati…

  17. comment
    Comment #11730614

    Agreed. I used to debug large "integration tests". Now with unit testing, I'm only debugging a bit of new code atop a foundation that is regularly unit tested.

  18. comment
    Comment #11621000

    I agree, CUDA took a step in the right direction by allowing annotated C++ source to be compiled for the device. As an HPC developer, I'm using the Kokkos C++ library https://githu…

  19. comment
    Comment #10245433

    I also work in HPC and have been doing a better job of this but still struggling in some areas. For example, the sin() and cos() implementations are different on some machines, and…

  20. comment
    Comment #9477760

    Well, Go and Rust can do better threading on this problem than a not-really-optimized C code with OpenMP. Thats a start. Message passing has to be shown next, and then one can deci…

  21. comment
    Comment #9477190

    In order for a language to replace C, it has to do two things: 1) be able to write an OS kernel competitive with Linux in this language. 2) get its compiler(s) ported to new archit…