32bit jail on 64bit FreeBSD
Sometimes it can be necessary or preferable to run software in 32bit versions, even if the OS is 64bit (i.e. running the i386-version on amd64 OS). As an example, software with deep memory structures mainly consisting of pointers, such as dictionaries of dictionaries of light-weight objects, will occupy almost twice the RAM on a 64bit OS. If multiple instances of, say, 3GB memory structures are needed, the 64bit penalty quickly adds up. ...