Hi
i want to limit ram usage of one user with /etc/limits.conf
the problem is that i don't know which parameter is for ram.
is it
or it's other parameters.

I don't think you can (with limits.conf).

The correct parameter would be rss, but I think that is not implemented.

thanks for reply.
well rss is unusable in kernel above 2.4.30.

from limits.conf man page :

How about

thanks.
i will test it and put results here.

i put this limit as hard limit but user cant even open vi or nano and get this error:

I think you are limiting virtual memory per process for a user, when you want to limit physical ram total (across processes) for that user.

If you use virtual memory as a limit on physical ram, you can't set the limit with any accuracy. Some processes might use as much physical ram as they use virtual memory, so a higher limit on virtual would let them use more physical than you want. Other processes (as you seem to have discovered already) use a small fraction physical ram for a large amount of virtual. Stopping them from doing so stops them from running at all, even if running them unlimited would have used very little physical ram.

Pre user across multiple processes is also hard to do. The relevant limits are per process for the specified user.

If I knew the solution, I would tell you. I'm posting to explain that the place you are looking for the solution is further from a real solution than it might appear.

From what I understand you have to isolate every user in a virtual environment using virtual technology. Something that cloudlinux make capable. I could be wrong though. There may be other ways.