marblestation

benchmark-leapfrog

Fortran2017–2017

marblestation / benchmark-leapfrog

benchmark-leapfrog

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Observed mentions: 2017-02-13 08:46:36 UTC to 2017-02-13 14:34:53 UTC.

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Period	Start (UTC)	End (exclusive, UTC)	Mentions	Comments
Feb 13, 08:00	2017-02-13 08:00:00 UTC	2017-02-13 09:00:00 UTC	3	3
Feb 13, 09:00	2017-02-13 09:00:00 UTC	2017-02-13 10:00:00 UTC	0	0
Feb 13, 10:00	2017-02-13 10:00:00 UTC	2017-02-13 11:00:00 UTC	0	0
Feb 13, 11:00	2017-02-13 11:00:00 UTC	2017-02-13 12:00:00 UTC	1	1
Feb 13, 12:00	2017-02-13 12:00:00 UTC	2017-02-13 13:00:00 UTC	1	1
Feb 13, 13:00	2017-02-13 13:00:00 UTC	2017-02-13 14:00:00 UTC	0	0
Feb 13, 14:00	2017-02-13 14:00:00 UTC	2017-02-13 15:00:00 UTC	2	2

What Hacker News says

7 sources

542458·Feb 13, 2017

> meaningful data to test that software runs correctly It appears that it doesn't run correctly (rust optimizes out the actual integration, and values are all set to NaN!) https://github.com/marblestation/benchmark-leapfrog/issues/6

In What can Rust do for astrophysics?

Devid2014·Feb 13, 2017

https://github.com/marblestation/benchmark-leapfrog This are not valid benchmarks at all. What is the point to run N-Body sim with all particles set to 0.0 ? Where is the result of the sim ? Why it will be not validated at all ? To make this look like real benchmark one will need to use the same start condition and then validate that result for all languages is the same. It would be great to have C++ code using Eigen library for example ? To show the difference . Also this is naive O(N^2) sim that could be speed up using Fast multipole method (FMM), but of course this would be much more complicated to do this in Rust or Go as in C++.

In What can Rust do for astrophysics?

michaf·Feb 13, 2017

This seems to have been fixed 3 hours ago: https://github.com/marblestation/benchmark-leapfrog/commit/c...

In What can Rust do for astrophysics?

tom_mellior·Feb 13, 2017

> If I put a println!("{}", x[0][0]) at the end, I end up with 1m43s. Yes, without that it's basically cheating. There is now a GitHub issue: https://github.com/marblestation/benchmark-leapfrog/issues/6 The submitter writes: "final output [for Rust] is 134 seconds, and also the output is [[NaN, NaN, NaN], [NaN, NaN, NaN]] (batman)"

In What can Rust do for astrophysics?

marblestation·Feb 13, 2017

We do not claim that Rust is so much performant than C, we just showed that Rust can be as fast as Fortran or C. And indeed, there must be something wrong with the C implementation. Pull requests with improvements are welcome: https://github.com/marblestation/benchmark-leapfrog

In What can Rust do for astrophysics?

marblestation·Feb 13, 2017

The code is available here: https://github.com/marblestation/benchmark-leapfrog It would be great if somebody have a fresh look at the C version, since I completely agree that it is not normal that its execution time is so far away from Fortran or Rust.

In What can Rust do for astrophysics?

marblestation·Feb 13, 2017

You can find the code for the simple N-Body implemented in different languages here (the more advanced N-Body version with tides has not been released yet): https://github.com/marblestation/benchmark-leapfrog And indeed, Fortran has decades of advantage in terms of libraries.

In What can Rust do for astrophysics?