views:

805

answers:

2

Title says it all.

Though the manual says you're better off to avoid a function call, I've also read $array[] is much slower than array_push(). Does anyone have any clarifications or benchmarks?

Thank you!

+18  A: 

No benchmarks, but I personally feel like $array[] is cleaner to look at, and honestly splitting hairs over milliseconds is pretty irrelevant unless you plan on appending hundreds of thousands of strings to your array.

Edit: Ran this code:

$t = microtime(true);
$array = array();
for($i = 0; $i < 10000; $i++) {
    $array[] = $i;
}
print microtime(true) - $t;
print '<br>';
$t = microtime(true);
$array = array();
for($i = 0; $i < 10000; $i++) {
    array_push($array, $i);
}
print microtime(true) - $t;

The first method using $array[] is almost 50% faster than the second one.

Some benchmark results:

Run 1
0.0054171085357666 // array_push
0.0028800964355469 // array[]

Run 2
0.0054559707641602 // array_push
0.002892017364502 // array[]

Run 3
0.0055501461029053 // array_push
0.0028610229492188 // array[]

This shouldn't be surprising, as the PHP manual notes this:

If you use array_push() to add one element to the array it's better to use $array[] = because in that way there is no overhead of calling a function.

The way it is phrased I wouldn't be surprised if array_push is more efficient when adding multiple values. EDIT: Out of curiosity, did some further testing, and even for a large amount of additions, individual $array[] calls are faster than one big array_push. Interesting.

Paolo Bergantino
I just always prefer to know which is the fastest way so when the day comes I will be asked to produce a high traffic site, I'll have some insight. Thanks for the answer.
alex
Micro-optimisations like these are rarely worth the effort. If you are writing it from scratch, do it how makes most sense, and only then, if it's a little slow to produce a page, profile it. The chances of getting all the way down to having to change something like this to speed things up is slight.
Alister Bulman
+2  A: 

Word on the street is that [] is faster because no overhead for the function call. Plus, no one really likes PHP's array functions...

"Is it...haystack, needle....or is it needle haystack...ah, f*** it...[] = "

Typeoneerror
Huh? PHP's array functions are awesome.
cletus
Functionally they are awesome, yes, but he was referring to the inconsistent naming scheme.
ryeguy
You should turn on parameter hinting in your IDE. But I agree, some consistency would have been great.
Pim Jager
Yeh I'd spend quite a bit more time on php's manual were it not for parameter hinting.. or intellisense as some programs call it I believe?
alex