Increase it, but don't set it too very large values unless you absolutely have to.
This parameter was created to stop PHP scripts from going "out of control".
For example, if you accedently put:
$a=0;
while ($a<5)
{
#blabla
$a=4;
};
Then every time you run the script it would keep running forever, and eventually you'd have so many processes running that your server would crash.