Lately I've noticing entries like this one in the kern.log of one of my servers:
Feb 16 00:24:05 aramis kernel: swapper: page allocation failure. order:0, mode:0x20
This is what I'd like to know:
- What exactly does that message mean?
- Is my server running out of memory?
The swap usage is quite low (less than 10%), and so far I haven't noticed any processes being killed because of lack of memory.
- The server is a Xen instance (DomU) running Debian 6.0
- It has 512 MB of RAM and a 512 MB swap partition
- CPU load inside the virtual machine shows an average of 0.25