NYCPHP Meetup

[Hans Zaunere]

> Does anyone know how the PHP Interpreter pulls switch/case statements
> together?  Does it emulate a C compiler and, for larger case sets,
> build a huge if/else cascade? Does it do this always?  Is there any way

Since PHP isn't really compiled, there are some inefficiencies when compared
with something like C.  I don't remember the exact mechanics, but switch is
generally slower than if/else and less optimizable (word?) when it comes to
opcode caching/etc..

> to know when it builds a jump table (like a s/c is supposed to)?  I've
> got a slow script (it's eating ~85% of execution time) that I can't
> work around and one of the slower parts is a switch case (which is
> slightly faster than manually building an if/else cascade) and was
> wondering if anyone had any performance tips for cases like these.

How many cases do you have?  Could you refactor into a loop?  Are you doing
string comparisons, or can they be converted to numeric tests?  Could some
of the logic be reduced/spread out into a database or some other process?

H