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.
