On Fri, Dec 24, 2010 at 7:32 PM, Alan Busby <thebu...@thebusby.com> wrote:
> On Fri, Dec 24, 2010 at 7:10 PM, Devrim Baris Acar
> <devrimba...@gmail.com>wrote:
>
>> I guess it would be a better guess if you could includethe cpu type/speed
>> for a rough reference...
>
>
> It was on an Intel Xeon E5410 (2.33GHz), though like others have already
> said there are a number of factors that affect performance. I was simply
> curious of the relative speeds of the various code snippets on a production
> server.
>
> Also, I tried the C version using unsigned long long ints (64bit) and it
> was roughly the same speed.
>
On OS X at least the following program shows identical performance to the
JVM using 64 bit integers, ~2000 nanoseconds on my machine. So Clojure is
not too far behind.
#import <Foundation/Foundation.h>
#include "stdio.h"
long long count_chars(const char* s) {
long long count = 0;
long long i;
for(i=0; s[i]; s++) {
if(s[i] != 32) {
count++;
}
}
return count;
}
int main(int argc, char** argv) {
const char *s = "This is a really long stringThis is a really long
stringThis is a really long stringThis is a really long stringThis is a
really long stringThis is a really long stringThis is a really long
stringThis is a really long stringThis is a really long stringThis is a
really long stringThis is a really long stringThis is a really long
stringThis is a really long stringThis is a really long stringThis is a
really long stringThis is a really long stringThis is a really long
stringThis is a really long stringThis is a really long stringThis is a
really long string";
long long i;
long long j;
for(j = 0; j < 10; j++) {
uint64_t start = mach_absolute_time();
for(i = 0; i < 1000; i++) {
count_chars(s);
}
uint64_t end = mach_absolute_time();
printf("%Lf nanoseconds\n", ((long double) end-start) / 1000.0);
}
exit(0);
}
David
--
You received this message because you are subscribed to the Google
Groups "Clojure" group.
To post to this group, send email to clojure@googlegroups.com
Note that posts from new members are moderated - please be patient with your
first post.
To unsubscribe from this group, send email to
clojure+unsubscr...@googlegroups.com
For more options, visit this group at
http://groups.google.com/group/clojure?hl=en
