D looses in speed to Common Lisp

[Daniel Kozák via Digitalmars-d]

On Mon, 11 May 2015 23:32:47 +0000
Dzhon Smit via Digitalmars-d <digitalmars-d at puremagic.com> wrote:

> On Monday, 11 May 2015 at 22:22:23 UTC, anonymous wrote:
> > On Monday, 11 May 2015 at 21:15:33 UTC, Dzhon Smit wrote:
> >> Tests on my machine:
> >> [code]$ time ./fib
> >> 0
> >>
> >> real    0m6.458s
> >> user    0m2.250s
> >> sys     0m0.933s
> >> $ time sbcl --dynamic-space-size 4GB --script fib.lisp
> >> 0
> >>
> >> real    0m1.884s
> >> user    0m1.290s
> >> sys     0m0.260s[/code]
> >
> > Can't confirm that. Times for me (linux x86_64):
> >
> > ----
> > $ dmd fib.d && time ./fib
> > 0
> >
> > real    0m2.410s
> > user    0m1.844s
> > sys     0m0.558s
> >
> > $ time sbcl --dynamic-space-size 4GB --script fib.lisp
> > 0
> >
> > real    0m2.659s
> > user    0m2.144s
> > sys     0m0.506s
> > ----
> >
> > As usual, ldc produces a faster binary than dmd:
> >
> > ----
> > $ ldc2 fib.d && time ./fib
> > 0
> >
> > real    0m1.900s
> > user    0m1.396s
> > sys     0m0.499s
> > ----
> >
> > Optimization flags don't seem to matter much for this program.
> 
> Could you re-run sbcl?  The first time it runs it creates fasls, 
> and afterwards it reuses them.  Probably you shouldn't include 
> the compile time for dmd either.
> 
> > import std.stdio, std.bigint;
> > import std.range;
> > import std.algorithm;
> > 
> > void main() {
> > 
> >     int n = 100000;
> >     auto sumFib1 = recurrence!("a[n-1] + a[n-2]")(BigInt(0),
> >             BigInt(1)).take(n).sum;
> >     auto sumFib2 = recurrence!("a[n-1] + a[n-2]")(BigInt(0),
> >             BigInt(1)).take(n).sum;
> > 
> >     writeln(sumFib2 - sumFib1); // 0
> > }
> 
> The point was to compare the performance of nearly identical 
> pieces of code in D and in CL.  However, when I compile this 
> idiomatic sample with `dmd fib2`, I get
> 
> $ time ./fib2
> 0
> 
> real    0m2.226s
> user    0m2.223s
> sys     0m0.003s
> 
> which is still slower.

This is wierd, you probably enable debug or I do not belive your
timing. Even with dmd (not ldc or gdc) I get better timing for D
idiomatic code than lisp version.

$ time sbcl --dynamic-space-size 4GB --script fib.lisp
0

real	0m2.263s
user	0m1.337s
sys	0m0.917s

[kozak at dajinka ~]$ dmd test.d 
[kozak at dajinka ~]$ time ./test
0

real	0m1.883s
user	0m1.873s
sys	0m0.003s

[kozak at dajinka ~]$ ldc test.d 
[kozak at dajinka ~]$ time ./test
0

real	0m1.311s
user	0m1.310s
sys	0m0.000s

[kozak at dajinka ~]$ gdc -o test test.d 
[kozak at dajinka ~]$ time ./test
0

real	0m1.447s
user	0m1.440s
sys	0m0.003s

[kozak at dajinka ~]$ dmd -debug test.d 
[kozak at dajinka ~]$ time ./test
0

real	0m3.816s
user	0m3.797s
sys	0m0.010s