Use ini_set("memory_limit", ...) without memory allocation

How I can use ini_set("memory_limit","some_number") in PHP to only set maximum memory limit for that php p开发者_如何学Crocess, not allocate that memory?

I don't think there's a need to prevent allocation of the memory.

Even if the PHP interpreter would start out with a big malloc() (which I doubt) then still the memory is only really allocated as soon as the process starts using it.

A related phenomenon is called overcommitment, there's a few good topics about it here on SO.

something good to read Memory Management with PHP

http://www.informit.com/articles/article.aspx?p=516587

If you explain more about your situation and what you exactly need, then may be more answers you can expect