On Mon, May 16, 2005 at 05:35:43PM -0400, DJ Delorie wrote: > > > What I have problem understanding is the last sentence of this > > paragraph in the light of your claim that it will results in > > swapping especially when we consider developers' machines with > > 512MB/1GB RAM, i.e. machines where memory is not "tight". > > Sigh, Linux works the same way. Processes can exceed their HARD > ulimit if there happens to be memory available, making RLIMIT_RSS > basically useless.
The Linux kernel has a boot-time option that you can use to lie to your kernel about how much physical memory you have. If the number you give is too high, you will eventually crash, but if it is too low, you can test how well your system would behave if it had less memory. It was originally there because the BIOS call that Linux used to use could only report a value up to 64m, so if you had more you had to let the kernel know. That problem was fixed long ago. So you can say "mem=128m" or the like. See http://www.faqs.org/docs/Linux-HOWTO/BootPrompt-HOWTO.html
