I doubt that rand(Bool) is any slower, since randbool() calls rand(Bool). It is worth filing this as a performance regression.
-viral On Monday, January 5, 2015 9:41:45 PM UTC+5:30, lapeyre....@gmail.com wrote: > > It may be in part the implementation of the RNG. I think it is also in > part whether the abstraction is optimized away. > Notice that Julia v0.3 is faster than v0.4. This is probably randbool() > vs. rand(Bool). > > On Monday, January 5, 2015 4:50:56 PM UTC+1, Isaiah wrote: >> >> Very neat. Just in case this gets posted to the interwebz, it is worth >> pointing out that the performance advantage for Julia can probably be >> explained by differences in the underlying RNG. We use dsFMT, which is >> known to be one of (if not the?) fastest MT libraries around. I could not >> find any published comparisons in a quick google, but based on this test >> harness [1], dsFMT may be significantly faster than std::mt19937: >> >> ``` >> ihnorton@julia:~/tmp/cpp-random-test$ ./random-real >> C++11 : 2.34846 >> Boost : 0.371674 >> dSFMT : 0.281255 >> GSL : 0.649981 >> ``` >> >> [1] https://github.com/yomichi/cpp-random-test >> >> >> On Mon, Jan 5, 2015 at 10:12 AM, <lapeyre....@gmail.com> wrote: >> >>> Oh, and, (I forgot to mention!) the Julia code runs much faster. >>> >>> >>> On Monday, January 5, 2015 3:56:07 PM UTC+1, lapeyre....@gmail.com >>> wrote: >>>> >>>> Hi, here is a comparison of Julia and C++ for simulating a random walk >>>> <https://github.com/jlapeyre/ranwalk-Julia-vs-Cxx>. >>>> >>>> It is the first Julia program I wrote. I just pushed it to github. >>>> >>>> --John >>>> >>>> >>
