Hi,
http://www.libvirt.org/html/libvirt-libvirt.html#virNodeInfo says that memory size is in kilobytes, however when I use this call I get an answer in Megabytes, see below. The hypervisor has 16 GB of RAM.
$ python
Python 2.6.6 (r266:84292, Jul 10 2013, 22:48:45)
[GCC 4.4.7 20120313 (Red Hat 4.4.7-3)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import libvirt
>>> conn=libvirt.open("qemu+ssh://
xx@xx.xxx.com/system")
Enter passphrase for key '/home/xx/.ssh/id_rsa':
>>> hv_info=conn.getInfo()
>>> hv_info
['x86_64', 15919, 8, 3292, 1, 1, 4, 2]