FYI: RHEL 7.3 does not suffer from this problem and appears to have ballooning enabled:
$ grep CONFIG_XEN_BALLOON /boot/config-3.10.0-514.el7.x86_64 CONFIG_XEN_BALLOON=y # CONFIG_XEN_BALLOON_MEMORY_HOTPLUG is not set
$ uname -a Linux cassandra-a-2 3.10.0-514.el7.x86_64 #1 SMP Wed Oct 19 11:24:13 EDT 2016 x86_64 x86_64 x86_64 GNU/Linux
$ cat /etc/redhat-release Red Hat Enterprise Linux Server release 7.3 (Maipo)
FYI: RHEL 7.3 does not suffer from this problem and appears to have ballooning enabled:
$ grep CONFIG_XEN_BALLOON /boot/config- 3.10.0- 514.el7. x86_64 XEN_BALLOON= y XEN_BALLOON_ MEMORY_ HOTPLUG is not set
CONFIG_
# CONFIG_
$ uname -a 514.el7. x86_64 #1 SMP Wed Oct 19 11:24:13 EDT 2016 x86_64 x86_64 x86_64 GNU/Linux
Linux cassandra-a-2 3.10.0-
$ cat /etc/redhat-release
Red Hat Enterprise Linux Server release 7.3 (Maipo)