The only guarantee is that double quotes will be slight slower if it contains 100s of variables to parse, or the string is really large i.e. in the 1Mb+ range.

It’s best to just use what you prefer and not to attempt to change the implementation of one to the other as there is a high chance of introducing regression bugs for a gain of no more then 1 or 2 request per second.

If you are having trouble explaining why register_globals is a bad thing, you can always explain that the new versions of php (version 6) will be completely removing this feature and that it’s a good idea to stop relying on it.

check out this site:

http://phpbench.com/

From the tests there, it looks like single quotes are slightly faster.

Early on in my PHP experience I’d read in several places that double quotes were more expensive because PHP always parsed them looking for vars that had to be defereferenced and converted to string content even if there were no embedded vars in the double-quoted string. They went on to say that PHP never parsed single-quoted strings for embedded vars, so using double quotes when there were no embedded vars was making PHP waste a lot of time parsing those strings for no reason.

Is there *any* truth behind this thinking or have I been the victim of cyber-legend?

TL

Wish I could do “SELECT * EXCEPT(`modified_date`, `amenities`,`client_id`) FROM mytable”
Because most of the time I do need the other 20+fields and future projects using most of the same code often call for the addition/removal of some fields and that would mean going back and editing the field select list in lots of places.

The google group thread on this just continues my years-long confusion about a few other things.
http://groups.google.com/group/make-the-web-faster/browse_thread/thread/ddfbe82dd80408cc

Is output buffering going to speed things up once and for all. I need a definitive answer on this from a reliable source or my boss will continue to forbid me from using ob_ functions. (He says it slows things down based on a comment he saw in php.ini.)

And if someone happens to have an unbelievably good article about why you shouldn’t do [? extract($_GET); extract($_POST); ?] at the start of every script I would be forever grateful. I’ve been trying for 3 years to convince him but that page on php.net about why register_globals is bad has had no effect on him.

take a look at this article: http://itst.net/654-php-on-fire-three-opcode-caches-compared

Ion Cube may not offer actual opcode optimization, but zend encoder does (~128% performance increase).

I have tried both eAccellerator and xCache, and they have major stability issues in a production environment.

IONCube and Zend Encoder are not op-code caches. They’re used to protect your code and have nothing to do with speeding it up.

I would of mentioned APC, eAccellerator and xCache