Re: 5x dom0 memory increase from Xen/Linux 3.4/2.6.18 to 4.1/3.0.0

[Anthony Wright <anthony@overnetdata.com>]

On 22/06/2011 15:39, Konrad Rzeszutek Wilk wrote:
> On Wed, Jun 22, 2011 at 03:22:30PM +0100, Anthony Wright wrote:
>> On 22/06/2011 14:32, Konrad Rzeszutek Wilk wrote:
>>> On Wed, Jun 22, 2011 at 02:15:35PM +0100, Anthony Wright wrote:
>>>> Maybe I'm misreading the output, but I couldn't see any numbers that
>>>> look like memory being assigned. I've attached the dmesg output. Do I
>>>> need to enable a CONFIG variable to get the output I need or am I
>>>> missing something.
>>> The memblock=debug should give you some idea of what is Reserved. The
>>> Reserved includes memory that is allocated by boot-time services (P2M,
>>> pagetables, NUMA) and by real reservations (for example ACPI space).
>>> Using the 'memblock=debug' can give you an idea of what services are
>>> reserving the most. Then we can narrow down who or what is eating the gobs
>>> of memory.
>>>
>>> see the 'Memory: ".. numbers. Also you might want to eliminate
>>> the balloon usage space algother by doing two things:
>>>
>>> Xen command line: dom0_mem=max:512MB
>>>
>>> Linux command line: mem=512MB
>>>
>>> That will effectivly remove any balloon space (so your Dom0 will _never_
>>> grow up).
>> The problem is I can't see any lines in the kernel dmesg output
>> (attached to previous email) that start "Memory: ", or anything else
>> that looks hopeful. Is there anything else I should add to the command
> dmesg | grep Memory: ?
Ok, I'm being really thick here, but I can't get the Memory: lines to be
output by the kernel. It looks like I can't get any KERN_INFO or
KERN_DEBUG lines to be output no matter what I do to log level. I'm not
much of a kernel hacker, but is there some debug code that I need to
enable to get these messages? I've wandered through google, and the
kernel code but I can't find anything obvious.

thanks,

Anthony.