"out of memory" error when starting Domain 0

"out of memory" error when starting Domain 0

[Ross C Mcilroy]

[-- Attachment #1: Type: text/plain, Size: 1961 bytes --]


Hi,

I'm about to start a Masters research project which will use Xen.  As such I'm trying to get it to work on my laptop (IBM T40).  I've built Xen 2.0.1 from the source tarball using the default .config file for the 2.6.9 kernel.  I'm using Suse 9.1 as the distribution on top.    

When I boot Xen, It seems to boot the Xen hypervisitor ok, then starts booting the linux kernel.  It gets as far as loading INIT, but then brings up an out of memory message:

  DMA per-cpu:
  cpu 0 hot: low 2, high 6, batch 1
  cpu 0 cold: low 0, high 2, batch 1
  Normal per-cpu: empty
  HighMem per-cpu: empty

  Free pages:     128kB (0kB HighMem)
  Active:642 inactive:1 dirty:0 writeback:0 unstable:0 free:32 slab:718 mapped:512 pagetables:87
  DMA free:128kB low 256kB high 384kB active:2348kB inactive:0kB present:16000kB
  protections[]: 0 0 0
  Normal free:0kB min:0kB low:0kB high:0kB active:0kB inactive:0kB present:0kB protections[]: 0 0 0
  HighMem free:0kB min:128kB low:256kB high384kB active:0kB inactive:0kB present:0kB protections[]: 0 0 0
  DMA: 2*4kB 1*8kB 1*16kB 3*32kB 0*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 128kB
  Normal: empty
  HighMem: empty
  Swap cache: add 0, delete 0, find 0/0, race 0+0
  Out of Memory: killing process 670 (hotplug)

It repeats this a number of times with different process numbers (but always hotplug), then it tries to kill INIT, then there are various other messages and it reboots because it can't find any other processes to kill.
 
Unfortunatly I don't have a null modem cable to save the boot messages on an other machine (the laptop doesn't even have a serial port), so I can't see all of the boot messages.

The grub entry for Xen is:

  title Xen 2.0 / XenLinux 2.6.9 (original)
    kernel (hd0,2)/boot/xen.gz dom0mem=131072
    module (hd0,2)/boot/vmlinuz-2.6.9-xen0 root=/dev/hda3 console=tty0


I would be very greatful for any help.

Thanks 

Ross

[-- Attachment #2: Type: text/html, Size: 2688 bytes --]

Re: "out of memory" error when starting Domain 0

[Jan Kundrát]

Ross C Mcilroy wrote:
> Unfortunatly I don't have a null modem cable to save the boot messages 
> on an other machine (the laptop doesn't even have a serial port), so I 
> can't see all of the boot messages.

Maybe CONFIG_NETCONSOLE could help you - look at 
Documentation/networking/netconsole.txt under linux kernel tree.

jkt

-- 
cd /local/pub && more beer > /dev/mouth



-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/

Re: "out of memory" error when starting Domain 0

[Robin Norwood]

"Ross C Mcilroy" <mcilrorc@dcs.gla.ac.uk> writes:
>
> The grub entry for Xen is:
>
>   title Xen 2.0 / XenLinux 2.6.9 (original)
>     kernel (hd0,2)/boot/xen.gz dom0mem=131072
>     module (hd0,2)/boot/vmlinuz-2.6.9-xen0 root=/dev/hda3 console=tty0

I don't know if this would be related at all, or if it is perhaps just
a cut-and-paste error, but according to the docs, the argument to the
kernel should be 'dom0_mem', not 'dom0mem'

-RN

-- 
Robin Norwood
Red Hat, Inc.

"The Sage does nothing, yet nothing remains undone."
-Lao Tzu, Te Tao Ching


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/

Re: "out of memory" error when starting Domain 0

[Keir Fraser]

> The grub entry for Xen is:
> 
>   title Xen 2.0 / XenLinux 2.6.9 (original)
>     kernel (hd0,2)/boot/xen.gz dom0mem=131072
>     module (hd0,2)/boot/vmlinuz-2.6.9-xen0 root=/dev/hda3 console=tty0
> 
> 
> I would be very greatful for any help.

It should be dom0_mem=131072, not dom0mem=131072! Because of this typo
Xen is using the default DOM0 size of 16MB which is too small to boot
most standard distro installations.

 -- Keir


-------------------------------------------------------
SF email is sponsored by - The IT Product Guide
Read honest & candid reviews on hundreds of IT Products from real users.
Discover which products truly live up to the hype. Start reading now. 
http://productguide.itmanagersjournal.com/

RE: "out of memory" error when starting Domain 0

[Ross C Mcilroy]

[-- Attachment #1: Type: text/plain, Size: 137 bytes --]


Thanks everyone, that was the problem.  I feel rather stupid, serves me right for printing the docs small to save paper I suppose :-)

[-- Attachment #2: Type: text/html, Size: 563 bytes --]