[Fedora-xen] HVM guests: Cannot allocate memory

[Felix Schwarz]

Hi,

my Dom0 is running with Fedora Core 6 and overall I would say it works. But I 
have a problem with HVM guests: I can start them just after system reboot but 
they won't start after I worked some time. "xm create" just gives me the error 
message "VmError: (12, 'Cannot allocate memory')".

The error does always appear when my "free" memory (as shown by top) is lower 
than the amount required by my HVM guest. What I do not understand is why Xen is 
not able to use memory which is used as cache by the Kernel. It is not uncommon 
for me to have 2-3 GB memory used as cache but only 20-30 MB free. Furthermore I 
expected that even SWAP can be used for my Xen guest which are another 2 GB.

Is there a workaround/bugreport for this behavior? Is there any hope it can be 
fixed?

fs