Hi Ian (and all),
I recently came across a bug in xl autoballooning in Xen 4.2.2 that I
found mentioned way back in May 2012.
In a nutshell, I tried to create a new DomU with 1024M of memory. The
Dom0 had 3100M free:
# xl info | grep memory
total_memory : 20479
free_memory : 3100
The guest template is very simple:
# cat /etc/xen/template.vm
name = "template.vm"
memory = 1024
vcpus = 1
cpus = "1-7"
disk = [ ''phy:/dev/vg_hosting/template.vm,xvda,w'' ]
vif = [ ''mac=20:34:01:36:02:54, vifname=vif.template,
bridge=br0'' ]
bootloader = "pygrub"
on_poweroff = ''destroy''
on_reboot = ''restart''
on_crash = ''restart''
When I tried to start the DomU, I got the following:
# xl create /etc/xen/template.vm -c
Parsing config from /etc/xen/template.vm
libxl: error: libxl.c:3437:libxl_set_memory_target: new target 18620 for
dom0 is below the minimum threshold
Setting autoballoon=0 in /etc/xen/xl.conf fixed the bug - however xl
shouldn''t even attempt to balloon the Dom0 when free_memory >
required
memory.
Thoughts?
--
Steven Haigh
Email: netwiz@crc.id.au
Web: https://www.crc.id.au
Phone: (03) 9001 6090 - 0412 935 897
Fax: (03) 8338 0299
