What's slowing for loops/assignment vs. C?
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by Lee
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Published on 2010-03-22T06:37:12Z
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2010/03/22
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I have a collection of PHP scripts that are extremely CPU intensive, juggling millions of calculations across hundreds of simultaneous users.
I'm trying to find a way to speed up the internals of PHP variable assignment, and looping sequences vs C.
Although PHP is obviously loosely typed, is there any way/extension to specifically assign type (assign, not cast, which seems even more expensive) in a C-style fashion?
Here's what I mean.
This is some dummy code in C:
#include <stdio.h>
int main() {
unsigned long add=0;
for(unsigned long x=0;x<100000000;x++) {
add = x*59328409238;
}
printf("x is %ld\n",add);
}
Pretty self-explanatory -- it loops 100 million times, multiples each iteration by an arbitrary number of some 59 billion, assigns it to a variable and prints it out.
On my Macbook, compiling it and running it produced:
lees-macbook-pro:Desktop lee$ time ./test2
x is 5932840864471590762
real 0m0.266s
user 0m0.253s
sys 0m0.002s
Pretty darn fast!
A similar script in PHP 5.3 CLI...
<?php
for($i=0;$i<100000000;$i++){
$a=$i*59328409238;
}
echo $a."\n";
?>
... produced:
lees-macbook-pro:Desktop lee$ time /Applications/XAMPP/xamppfiles/bin/php test3.php
5.93284086447E+18
real 0m22.837s
user 0m22.110s
sys 0m0.078s
Over 22 seconds vs 0.2!
I realize PHP is doing a heck of a lot more behind the scenes than this simple C program - but is there any way to make the PHP internals to behave more 'natively' on primitive types and loops?
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