Comment 5 for bug 997014

** Impact **

The current code in libvirt/connection.py does not compute the memory usage correctly when using Xen. It takes the information from /proc/meminfo whose information is not correct (at least for Xen 4.1.2 on Ubuntu). I've spotted the following situations:

 - No memory limit on the dom0. Whenever a machine is spawned, the dom0 memory might be ballooned down, so the memory reported by meminfo is also shrinked. This causes that the memory_mb column in the compute_nodes table changes.

 - Memory limit on the dom0 (i.e dom0_mem option in grub). Meminfo only shows the memory available for the dom0, but will not honour the total memory and the memory that is actually available for the domUs (xm info|grep memory).

** DevelopmentF Fix **

This has been addressed in development trunk: https://review.openstack.org/7296 and fixed in quantal.

** Stable Fix **

This has been addressed in stable/essex at: https://review.openstack.org/7789

** Test Case **

None

** Regression Potential **

None