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Robyn: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Robyn) — Mon, 02 Apr 2012 07:53:32 -0400

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Lyndon: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Lyndon) — Thu, 29 Mar 2012 08:56:37 -0400

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Alex: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Alex) — Tue, 06 Mar 2012 06:53:58 -0500

I was a bit surprized by the fact, so wandered if empty() gives some different results.

At the original test I added the following code:

$s = microtime(1);
for ($i = 0; $i < 100000; $i++) {
empty($arr['abracadabra']);
}
$e = microtime(1);
echo "empty: ".($e - $s)."\n";

The results I got on PHP 5.3.6-13ubuntu3.6 (with XCache v1.3.2, Xdebug v2.1.0, Suhosin v0.9.32.1)

isset: 0.05509090423584
array_key_exists: 0.22666001319885
empty: 0.023635864257812

Seva Lapsha: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Seva Lapsha) — Mon, 05 Mar 2012 04:36:17 -0500

In easytobook we had an edge case of average half a million loop cycles with 3-4 checks per cycle. We saved significant time not just on this example, but also on sacrificing the magic code in favor of public properties and explicit calls.

Nik: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Nik) — Sun, 04 Mar 2012 16:55:02 -0500

I always use this to replace the use of array_key_exists() alone:

if (isset(..) || array_key_exists(...))
{
...
}

It takes the performance advantage of isset() while keeping the NULL element detected correctly.

Detail explanation see this blog post:
http://www.zomeoff.com/php-fast-way-to-determine-a-key-elements-existance-in-an-array/

Dynom: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Dynom) — Sun, 04 Mar 2012 03:45:46 -0500

Hahaha, thanks for that. That just made my day.

Ilia Alshanetsky: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Ilia Alshanetsky) — Sat, 03 Mar 2012 12:54:32 -0500

That's a scary thought...

Stas: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Stas) — Sat, 03 Mar 2012 12:38:57 -0500

Do you hear that clicking? It is the sound of 1000s of application writers rewriting their key_exists to issets. Because now it's proven it is 10 times faster! So if my app is slow, it's because of that, not because I do a million of them each function call

Paul Reinheimer: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Paul Reinheimer) — Sat, 03 Mar 2012 12:11:52 -0500

funny this comes up now. I specifically called this out as something not to care about in my perf. talk

Jan Schneider: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Jan Schneider) — Sat, 03 Mar 2012 11:42:10 -0500

We noticed this already 9 years ago, granted this was back in PHP 4 days:
https://groups.google.com/forum/?fromgroups#!topic/mailing.www.horde-dev/a5D8ts2D67U
It even went into our coding standards: http://www.horde.org/apps/horde/docs/CODING_STANDARDS#existence-checking
I have to admit, we never ran a benchmark again, since this made it into our standard. But then again, we didn't have any reason to change what became second nature to us.

Ilia Alshanetsky: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Ilia Alshanetsky) — Sat, 03 Mar 2012 10:53:56 -0500

PHP 5.3 is a little slower, but not a whole lot, the same code on 5.3 took about the same time to run.

PHP 5.3:
Isset: 0.0249950885773
array_key_exists: 0.0579879283905

Colin Mollenhour: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Colin Mollenhour) — Sat, 03 Mar 2012 10:52:18 -0500

50k calls in one request? What on earth is it doing? It is great to know that PHP 5.4 makes such an improvement though!

Pierrick: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Pierrick) — Sat, 03 Mar 2012 10:48:52 -0500

Héhé this explain that always try to do your microbench with php -n

Ilia Alshanetsky: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Ilia Alshanetsky) — Sat, 03 Mar 2012 10:45:18 -0500

Fixed the minutes vs seconds, still on 5.4 and 5.3, all I can see is a 2.5 speed difference and both operations are exceptionally fast.

Ilia Alshanetsky: Performance Analysis of isset() vs array_key_exists()

nospam@example.com (Ilia Alshanetsky) — Sat, 03 Mar 2012 10:43:48 -0500

I ran the code on PHP 5.3.8 and the results were largely the same.