I noticed that firefox sometimes uses a lot of memory. Can something like setrlimit be used to control it? I tried to use it on the command line, but it didn't work.
I'm not sure if this is a good idea. If Firefox reaches the memory limit, it may crash instead of continuing to run with no new tabs or other content (the behavior you appear to be expecting). – DragonLordApr 26 '11 at 5:04