Execution speed of PHP

jcs

I just started with PHP (3 days) as I was suprised when somebody told me he had optimized a php library for speed by putting everything on one line.

So is one line PHP faster then readable multiline/indended code?

Johan

ahundiak

Back in the days or yore (before PHP3) there was actually some validity for this technique.

Back then, php continuely parsed as it executed. So code in a loop was being parsed over and over. It's barely possible that in some cases one could notice a tiny improvement in speed by stripping out all new lines and comments.

Nowadays, the code is only parsed once and the oeverhead of skipping new lines would be almost impossible to notice.

If you were going to try this technique then I would suggest writing your code in the normal fashion then using a filter of some sort to strip out the new lines when copying the file to your actual web site.

suntra

You can put it in one line, but that's very not useful when you have a bug !!! I really suggest you to put it line by line and don't be shy to use TAB !

Example :

<?
 $myvariable	= true;
 $mynumber		= 56;
 if($myvariable == true) {
 	echo "myvariable is true<BR/>\n";
 } else {
 	for($i = 0; $i < 100; $i++) {
 		if($i == $mynumber) {
 			$myvariable = $i;
 			break;
 		}
 	}
 	echo "myvariable is $myvariable<BR/>\n";
 }
?>

And not something like this :

<?
 $myvariable	= true;
 $mynumber		= 56;
 if($myvariable == true) {
 echo "myvariable is true<BR/>\n";
 } else {
 for($i = 0; $i < 100; $i++) {
 if($i == $mynumber) {
 $myvariable = $i;
 break;
 }
 }
 echo "myvariable is $myvariable<BR/>\n";
 }
?>

jcs

Originally posted by ahundiak
Back in the days or yore (before PHP3) there was actually some validity for this technique.

Back then, php continuely parsed as it executed. So code in a loop was being parsed over and over. It's barely possible that in some cases one could notice a tiny improvement in speed by stripping out all new lines and comments.

Nowadays, the code is only parsed once and the oeverhead of skipping new lines would be almost impossible to notice.

If you were going to try this technique then I would suggest writing your code in the normal fashion then using a filter of some sort to strip out the new lines when copying the file to your actual web site.

Thanks, but someone did this telling me of the great speed improvement. But as I thougth it is bull.

edwardsbc

The biggest speed "improvements" usually just come from better understanding what PHP is doing in the code. Let the PHP authors worry about the actual executable code optimization. You should worry about using the best structures and syntax in your PHP script.

I write code with lots of loops which build html tables. I experienced significant performace gains when I quit using double quotes for everything. Single quotes are not scanned by the PHP engine and are thus traversed faster.

Compare:

echo "Fixed text that never changes. A $variable, and $another";

echo 'Fixed text that never changes. A ',$variable, ' and ',$another;

And yes that is a comma. Concatenation (using a period) takes extra time!

I'm sure there are other tips, I'll let other experts add them. This is just something I think many beginners could benefit from.