File xl-conf-disable-autoballoon.patch of Package xen.23269
--- xen-4.12.0-testing/tools/examples/xl.conf.orig 2019-03-11 06:17:17.586380817 -0600
+++ xen-4.12.0-testing/tools/examples/xl.conf 2019-03-11 06:17:31.314553910 -0600
@@ -3,7 +3,7 @@
# Control whether dom0 is ballooned down when xen doesn't have enough
# free memory to create a domain. "auto" means only balloon if dom0
# starts with all the host's memory.
-#autoballoon="auto"
+autoballoon="off"
# full path of the lockfile used by xl during domain creation
#lockfile="/var/lock/xl"