1.11 Managing Domain 0 Memory

When the host is set up, a percentage of system memory is reserved for the hypervisor, and all remaining memory is automatically allocated to the host’s desktop environment (domain 0).

A better solution is to set a minimum amount and a maximum amout of memory for domain 0 so that memory is more appropriately allocated to the hypervisor. A good maximum amount is 20 percent of total system memory up to 2 GB. A good minimum amount is at least 256 MB.

1.11.1 Setting a Maximum Amount of Memory

  1. Determine the amount of memory to set for domain 0.

  2. At the host desktop, type xm list to view the currently allocated memory.

  3. Run YaST > Boot Loader.

  4. Select the Xen section.

    Figure 1-8 Boot Loader Settings: Section Management

  5. In Additional Xen Hypervisor Parameters, add dom0_mem= mem_amount where mem_amount is the maximum amount of memory to allocate to the host desktop (domain 0). Add K, M, or G, to specify the size, for example, dom0_mem=768M.

  6. Restart the computer to apply the changes.

1.11.2 Setting a Minimum Amount of Memory

To set a minimum amount of memory for the host desktop (domain 0), edit the dom0-min-mem parameter in the xend-config.sxp file and restart xend. For more information, see Section 1.2, xend.