5 ms·

> .. you can write vastly more complicated programs that are, say, 80% as fast as hand-optimized C for only 10% of the effort of hand-optimized C. I don't mean

> .. you can write vastly more complicated programs that are, say, 80% as fast as hand-optimized C for only 10% of the effort of hand-optimized C. I don't mean to be personal, but your quantative claim smells a little like unsubstantiated BS. Do you have any data to back it up? > That said, Haskell performs pretty well in the toy benchmarks anyway. Currently, "pretty well" looks like GHC performance is 50% to 10% of hand-crafted C using perhaps 5 times as much memory. (If the GHC program builds at all that is.) fannkuch-redux Haskell GHC: 16.70 sec 7,628 mem C gcc: 8.97 sec 1,660 mem spectral-norm Haskell GHC: 4.06 sec, 9,880 mem C gcc: 1.99 sec, 1,824 mem n-body Haskell GHC: 24.48 sec, 6,468 mem C gcc: 9.96 sec, 1,016 mem reverse-complement Haskell GHC: 1.39 sec, 132,176 mem C gcc: 0.42 sec, 143,948 mem mandelbrot Haskell GHC: 11.64 sec, 41,180 mem C gcc: 1.65 sec, 32,684 mem fasta Haskell GHC: 14.68 sec, 455,088 mem C gcc: 1.33 sec, 2,856 mem binary-trees Haskell GHC: 26.28 sec 511,444 mem C gcc: 2.38 sec 131,728 mem k-nucleotide Haskell GHC: Make Error C gcc 0.06 sec ? mem pidigits Haskell GHC: Make Error C gcc: 0.06 sec ? mem regex-redux Haskell GHC: Make Error C gcc: 0.02 sec ? mem Haskell GHC: The Glorious Glasgow Haskell Compilation System, version 8.0.2 C gcc: gcc (Ubuntu 6.3.0-12ubuntu2) 6.3.0 20170406

Tarean 9y ago
The make errors are a bit weird because the programs build on my machine no problem. In parts haskells slowness seems to be because no one cares enough to work on it. Can't say for sure, though, so maybe I just should try a task and implement it to see how fast it'd be without amazing optimization foo. Although of course these benchmarks aren't really representative of the real world because they'd just end up as a c ffi call in most languages if they actually were that performance critical.
- delhanty 9y ago
  I agree with all that, particularly the bit about the c ffi call. It's more relevant to compare Rust with C and C++, as Rust is a language that could reasonably display C for the ffi call. But then remember that @wyager is claiming >80% as fast as hand-optimized C for only 10% of the effort of hand-optimized C If it's really only 10% of the effort then one shouldn't really have "to work on it" to get semi-decent performance. A more modest claim of say: 50% as fast as hand-optimized C for only 20% of the effort of hand-optimized C would have been more credible and still a big win for many use cases.
  - Tarean 9y ago
    Tried my hand at the knucleotide[1] one. Lifted the algorithm from the fastest rust solution. As optimization I dropped some Unpack pragmas and strictness annotations, used Data.Hashtable.Cuckoo for in-place updating hash tables because that seemed necessary for the task, and added naive parallelization via let outputs = map (exec content) tasks `using` parList rseq That got around 24 seconds which seems acceptable for a fairly straightforward solution that is around half the size of the rust one I copied. Might try to optimize later. [1]: http://benchmarksgame.alioth.debian.org/u64q/knucleotide.html http://benchmarksgame.alioth.debian.org/u64q/knucleotide.htm...
    - igouy 9y ago
      http://benchmarksgame.alioth.debian.org/play.html http://benchmarksgame.alioth.debian.org/play.html
- igouy 9y ago
  That pi-digits program does not "build on [your] machine no problem". It cannot. The line "main = putStr.pidgits.read.head =<< getArgs" has been commented out because the program author has optimised-away some of the work that must be done.
  - Tarean 9y ago
    Fair enough, I only checked the two knucleotide programs which both failed because of missing dependencies.
- igouy 9y ago
  >> The make errors are a bit weird because the programs build on my machine no problem. << My fault (except for pi-digits and regex-redux). I neglected to work-through the force-reinstalls that inevitably follow my update of the GHC compiler. Done.

Tarean 9y ago

The make errors are a bit weird because the programs build on my machine no problem. In parts haskells slowness seems to be because no one cares enough to work on it. Can't say for sure, though, so maybe I just should try a task and implement it to see how fast it'd be without amazing optimization foo. Although of course these benchmarks aren't really representative of the real world because they'd just end up as a c ffi call in most languages if they actually were that performance critical.

delhanty 9y ago
I agree with all that, particularly the bit about the c ffi call. It's more relevant to compare Rust with C and C++, as Rust is a language that could reasonably display C for the ffi call. But then remember that @wyager is claiming >80% as fast as hand-optimized C for only 10% of the effort of hand-optimized C If it's really only 10% of the effort then one shouldn't really have "to work on it" to get semi-decent performance. A more modest claim of say: 50% as fast as hand-optimized C for only 20% of the effort of hand-optimized C would have been more credible and still a big win for many use cases.
- Tarean 9y ago
  Tried my hand at the knucleotide[1] one. Lifted the algorithm from the fastest rust solution. As optimization I dropped some Unpack pragmas and strictness annotations, used Data.Hashtable.Cuckoo for in-place updating hash tables because that seemed necessary for the task, and added naive parallelization via let outputs = map (exec content) tasks `using` parList rseq That got around 24 seconds which seems acceptable for a fairly straightforward solution that is around half the size of the rust one I copied. Might try to optimize later. [1]: http://benchmarksgame.alioth.debian.org/u64q/knucleotide.html http://benchmarksgame.alioth.debian.org/u64q/knucleotide.htm...
  - igouy 9y ago
    http://benchmarksgame.alioth.debian.org/play.html http://benchmarksgame.alioth.debian.org/play.html
igouy 9y ago
That pi-digits program does not "build on [your] machine no problem". It cannot. The line "main = putStr.pidgits.read.head =<< getArgs" has been commented out because the program author has optimised-away some of the work that must be done.
- Tarean 9y ago
  Fair enough, I only checked the two knucleotide programs which both failed because of missing dependencies.
igouy 9y ago
>> The make errors are a bit weird because the programs build on my machine no problem. << My fault (except for pi-digits and regex-redux). I neglected to work-through the force-reinstalls that inevitably follow my update of the GHC compiler. Done.