3.0.3-rc3 restore problem

3.0.3-rc3 restore problem

[Tuan Van]

Hi everyone,
I tried to restore a saved domain but it failed with:
Traceback (most recent call last):
  File "/usr/lib/python2.4/site-packages/xen/xend/XendDomain.py", line
263, in domain_restore_fd
    return XendCheckpoint.restore(self, fd)
  File "/usr/lib/python2.4/site-packages/xen/xend/XendCheckpoint.py",
line 150, in restore
    balloon.free(xc.pages_to_kib(nr_pfns))
  File "/usr/lib/python2.4/site-packages/xen/xend/balloon.py", line 166,
in free
    raise VmError(
VmError: I need 192512 KiB, but dom0_min_mem is 200704 and shrinking to
200704 KiB would leave only 119668 KiB free.

For some reason, balloon.py get the wrong value for dom0_min_mem. In
grub.conf I set dom0_mem=131072 and xm list shows it correctly:
# xm list 0
Name                                      ID Mem(MiB) VCPUs State   Time(s)
Domain-0                                   0      128     1 r-----   4906.2

Did I miss something ?

Thanks,
Tuan

Re: 3.0.3-rc3 restore problem

[Keir Fraser]

On 12/10/06 17:52, "Tuan Van" <lang.thang@gmail.com> wrote:

> For some reason, balloon.py get the wrong value for dom0_min_mem. In
> grub.conf I set dom0_mem=131072 and xm list shows it correctly:
> # xm list 0
> Name                                      ID Mem(MiB) VCPUs State   Time(s)
> Domain-0                                   0      128     1 r-----   4906.2
> 
> Did I miss something ?

/etc/xen/xend-config.sxp. Change the dom0-min-mem parameter in there to
zero. If you know what you are doing then dom0 auto-ballooning is really
just a pain in the neck. Probably we should disable it by default if we see
an explicit dom0_mem= parameter on the Xen command line.

 -- Keir

Re: 3.0.3-rc3 restore problem

[Ewan Mellor]

On Thu, Oct 12, 2006 at 09:52:59AM -0700, Tuan Van wrote:

> Hi everyone,
> I tried to restore a saved domain but it failed with:
> Traceback (most recent call last):
>   File "/usr/lib/python2.4/site-packages/xen/xend/XendDomain.py", line
> 263, in domain_restore_fd
>     return XendCheckpoint.restore(self, fd)
>   File "/usr/lib/python2.4/site-packages/xen/xend/XendCheckpoint.py",
> line 150, in restore
>     balloon.free(xc.pages_to_kib(nr_pfns))
>   File "/usr/lib/python2.4/site-packages/xen/xend/balloon.py", line 166,
> in free
>     raise VmError(
> VmError: I need 192512 KiB, but dom0_min_mem is 200704 and shrinking to
> 200704 KiB would leave only 119668 KiB free.
> 
> For some reason, balloon.py get the wrong value for dom0_min_mem. In
> grub.conf I set dom0_mem=131072 and xm list shows it correctly:
> # xm list 0
> Name                                      ID Mem(MiB) VCPUs State   Time(s)
> Domain-0                                   0      128     1 r-----   4906.2
> 
> Did I miss something ?

dom0_min_mem is an additional setting in /etc/xen/xend-config.sxp,
over-and-above anything that might be set on the kernel command line
(dom0_mem).  You need to change that setting to match your dom0_mem (or make
it lower than dom0_mem, if that's what you'd like).

Ewan.