Comments on: PHP Performance Best Practices

By: Donovan Walker

Donovan Walker — Wed, 11 Nov 2009 22:05:14 +0000

Give the guy a break. He wrote it in 2005. Back then I don’t think Copy-on-Write was implemented. Glad you included the link.

By: Mathias Rav

Mathias Rav — Mon, 05 Oct 2009 18:53:47 +0000

“In PHP, $foo = $bar makes a copy of $bar, and stores it in $foo.”
As henrietta stated, you lie. http://blog.libssh2.org/index.php?/archives/51-Youre-being-lied-to..html

By: henrietta

henrietta — Thu, 19 Feb 2009 12:33:59 +0000

“”In PHP, $foo = $bar makes a copy of $bar, and stores it in $foo.”"

Yeah, but Zend Engine implements Copy-On-Write logic. As stated in a PHP documentation comment, in most cases the Zend Engine > you.

By: Ian

Ian — Wed, 30 Jul 2008 21:18:28 +0000

@James, If you have 30k LOC in one file, your concerns should be about the maintainability of your application, not performance.

Taking a speed hit in exchange for maintainability gains is a good trade-off. CPU cycles are cheap and only getting cheaper. Developer cycles are expensive and getting more so.

By: Martin Rusev Blog about web development and graphic design » Blog Archive » PHP performance tips around the web

Tue, 29 Jul 2008 08:15:23 +0000

[...] http://atomized.org/2005/04/php-performance-best-practices/ [...]

By: James

James — Mon, 28 Jul 2008 19:57:19 +0000

been looking around the web for a good article on performance tuning.

I have a script that is approximately 30,000 lines long (it’s a simulator)… I’ve recently begun to hack out logical pieces of the script and place them in separate files… as the script will run, it will include whatever applicable file is needed at that time.

I’ve read that having a massive number of includes can actually reduce performance due to file I/O delays.

At what point do the delays from the includes start to outweigh the parse time of a single large script?

By: kvz

kvz — Sat, 06 Oct 2007 16:03:30 +0000

Another article about optimizing the performance of apache & php for high traffic loads:
http://kevin.vanzonneveld.net/techblog/article/survive_heavy_traffic_with_your_webserver

By: TruePath

TruePath — Mon, 25 Jun 2007 22:00:16 +0000

So long as you aren’t modifying the arrays passing by reference shouldn’t be any faster. It is my understanding (from a comment posted in the PHP manual on references) that internally php always passes/assigns by reference adding appropriate copy on write flags so data can masquerade as a copy.

In any case it is far from clear that passing by reference results in better performance *unless* you want to modify the values in the array and have those changes show up in two places.

By: Ian Eure

Ian Eure — Tue, 06 Mar 2007 19:37:33 +0000

Hans,
Thanks for the feedback. I ran these tests a while back, and have not re-run them with PHP 5. The situation with some of these items has changed; for example, PHP 5 supports foreach by reference, which PHP 4 did not. The variability of these factors is precisely why I implore people to test different scenarios to find the best balance for their use-case.

You’re absolutely right that there is a trade-off of clarity vs. speed for string operations. It’s an individual choice as to whether it’s a win or not.

By: Hans Duedal

Hans Duedal — Tue, 06 Mar 2007 10:13:35 +0000

My studies of “string concatenation instead of sprintf()” show a 20% performance increase in favor of string concatenation. Not 100% as you mentioned. I many cases I would prefer sprintf for the clarity the syntax provides when the speed increase is no more than in average 20%.
This is testet on PHP 5.2.1 running in CLI mode on Ubuntu.