Re: Re: PHP Performance in Apache: Multi-Process vs Multi-Threaded

2010/12/15 Julien Pauli <jpauli@php.net> > > Well, I would say that if your problem is memory, you should consider > threads as they all share the same memory space in their process. > > Apache's children can weight very heavy if PHP's been compiled to > support lots of extensions, you can happen with ~40/50Mb per process > which is very huge. Considerating 50 parallel processes eat up 2-3Gb > for example. > Surely creating a fork of a 50MB process will not consume an additional 50MB because of copy-on-write virtual memory? I would think you would only see this growth in memory usage if the extensions maintained a large payload of data that was being heavily modified in each request, such as caches, but I expect they create their own shared memory segments (I have yet to check the source of APC). Jon