[fedora-virt] f12 guest memory problems?

[Gianluca Cecchi]

Hello,
F11 x86_64 + rawvirt with latest updates
I have a f12 near beta x86_64 kvm guest where now I'm doing "yum update" in
it and basically I'm only in gui session without doing anything else

Some strange things:
- in virt-manager set 400Mb for VM (both the allocated, change, max
allocation values... btw how to use them???)
my guest sees only about 330Mb
[gcecchi@localhost ~]$ free
             total       used       free     shared    buffers     cached
Mem:        344212     252944      91268          0       4268      26908
-/+ buffers/cache:     221768     122444
Swap:       950264     179092     771172

With dmesg on guest I see something like this:

Memory: 329452k/409536k   ...... 79696k reserved

The 79696k reserved seems to fill the gap...
is this a feature in f12 or based on it being a guest?

- As you see, the guest is swapping about 180Mb, and actually it is very
slowly responsive.
Shouldn't it use some of buffers/cache before swapping so much? Is this
expected during a yum update (only 34 packages for an overall of 72MB)?
Or problem with F12 itself or virtualization layer?

Thanks
Gianluca