Re: [ZEND-ENGINE-CVS] cvs: ZendEngine2 / zend_execute.c

On July 16, 2004 11:58 am, Thies C. Arntzen wrote: > hey ilia, > > here's another one of my meaningess, synthetic benchmarks (this is how > the CreatorsOfPHP(tm) would call them) > > ackermann(8) (source on request - highly recursive) Recursive functions in PHP are inherently dangerous as without proper limits they will rather quickly ~5671 iterations with a basic function a() { a(); } (PHP 4/5). By comparison the same code only takes 2897 iterations before the patch. While the patch does not solve this crash it reduces it's chances by nearly 50% (unexpected benefit). More over the crash problem that the patch solves is not theoretical that I made up because I have nothing better to do. We have at least 2 confirmed bug reports by different people and surely there are others who came across this issue and didn't report it. Yes, you are correct, with a dedicated benchmark specifically designed to "exploit" the allocation routine change there is a performance drop, but surely stability is more important then speed. If that is not that case, there are a whole lot of optimizations we can perform, but that'd mean users will need to write their code extra carefully :-), which as we know is not going to happen. Ilia