Xen: Unable to allocate memory

   So it was rather frustrating that after I got all of the domUs created and ready when I rebooted the machine it decided to not start 3 doms.  After talking with a colleague I was directed to the following page:

http://wiki.xensource.com/xenwiki/XenBestPractices

   In the above link it says to modify '/boot/grub/menu.lst' and add the following:

dom0_mem=512M loglvl=all guest_loglvl=all

   then you are to edit '/etc/xen/xend-config.sxp' and modify/add the follwoing:

(dom0-min-mem 512)
(enable-dom0-ballooning no)

   After setting these options you need to restart the machine and all of the domUs (5+) should start without any errors of "allocating memory"