Restricting available memory for testing on linux

Question

The machine on which I develop has more memory than the one on which the code will eventually run. I dont have access tothe machine on which it will actually run. This is a 64 bit application and I intend to use the address space but cap physical allocation. I dont want to lock down virtual memory, only physical memory. Is there a way to set limits on a linux machine such that it mimics a system with low RAM. I think ulimit does not differentiate between reserved address space vs actual allocation. If there is a way to do it without rebooting with different kernel parameters or, pulling out extra RAM that would be great. May be some /proc tricks.

Answer 1

If You can change boot command line of the kernel and want to restrict available memory use

mem=

boot parameter.

For more information check:

https://www.kernel.org/doc/html/latest/admin-guide/kernel-parameters.html

Answer 2

See https://unix.stackexchange.com/questions/44985/limit-memory-usage-for-a-single-linux-process which suggests using "timeout" from here: https://github.com/pshved/timeout .