In our current configuration, the dom0 kernel takes up all the memory available within the system on start up, and then assigns it out to the domUs as needed. When we create guest domains in this chapter we need a way to provide memory for each of the guest domains that we create. Xen provides a simple way to specify the memory used by the dom0 kernel a parameter to the hypervisor on start up. Modify the
/boot/grub/menu.lst in your base system and add an additional parameter to the kernel line specifying the amount of maximum memory that you want the dom0 kernel to use:
kernel /xen.gz noreboot dom0_mem=256M
On my system, I assigned a memory size of 256M to my dom0. If you are only going to manage a Xen host and will not have any ...