Memory is currently released very quickly when the object reach 0 refs. In high-throughput applications (such as a loadbalancer with a few thousand requests/second) it's very critical that data don't stay around more than a few ms, or the memory usage will increase rather rapidly.
The current gc, at least, is _way_ to slow at freeing things for it to be a suitable solution, the loadbalancer in question is actually likely to run out of addressing space or run gc very often. Not to mention that it can take up to a a second (or even several) for the gc to do it's job at times which is not really acceptable as long as it blocks the whole server, but that would be fixed with an asynchronous version. The loadbalancer and download servers for Opera Mini actually had disabled gc() totally since it sometimes hung the service for 10+ seconds, long enough to cause things to time out, but that seems to work better in newer versions of pike, so it's now enabled again
