it went away because it was resource expensive. even with copy-on-write semantics, those backend httpds with an entire perl runtime in each core were pretty hug

it went away because it was resource expensive. even with copy-on-write semantics, those backend httpds with an entire perl runtime in each core were pretty huge and inefficient. the models that replaced it were single process multiple threads and asynchronous (never block) models that didn't create or require one of many application processes per request. i think the choice of the preforking model was a stability and portability thing. if one of the children crashed it was no big deal, where a crash in a single process application or webserver will cause the everything to go down. also back in those days threading semantics varied widely between operating systems, the apis themselves differed and linuxthreads were just really too new to run in production.