Setting maxmem for a XEN DomU from command-line?

Question

It's actually quite simple: is there any way I can set maxmem at runtime from the command line? If I edit the .xsp files, how can I ensure they are being re-read by Xen?

Answer 1

# xm mem-max help
Error: 'xm mem-max' requires 2 arguments.

Usage: xm mem-max <Domain> <Mem>

Set the maximum amount reservation for a domain.

Make sure you change the .xsp in accordance so that it retains the new setting after reboot.

Answer 2

This depends on what your guest OS is, but I've read that the Linux kernel doesn't support ballooning its memory above the maxmem argument passed to the kernel at boot. My information might be out of date, though.