Re: Mid-term Update for Cycle Collector (Google Summer of Code Project)

On Sat, 14 Jul 2007, Rasmus Lerdorf wrote: > David Wang wrote: > >> Is it possible that total server throughput with gc could actually be > >> better than unmodified php by preventing swapping at some higher > >> level of concurrent requests? > > > > Yes, that's certainly true if it becomes the case that concurrent > > requests take up so much memory that they induce swapping! If that > > ever happens, the system will basically come to a complete standstill. > > No matter what the GC does, it still will be effectively infinitely > > faster than saving and retrieving information from the hard drive. > > It is still extremely rare for code to have cyclic references. So while > GC could prevent swapping in the case of a malicious user, or in the > case of a coding mistake, I don't think the general case of typical code > running under normal circumstances would consume less memory with GC > enabled. It all depends on the code of course - things that do parsing usually tend to have cyclic structures (to keep a link to the "parent"). Derick -- Derick Rethans http://derickrethans.nl | http://ez.no | http://xdebug.org