Re: a ton of kernel issues

[David Vrabel <david.vrabel@citrix.com>]

On 13/12/11 21:45, Konrad Rzeszutek Wilk wrote:
> On Wed, Dec 14, 2011 at 01:05:31AM +0400, George Shuklin wrote:
>>
>> On 13.12.2011 17:17, David Vrabel wrote:
>>>>>> pv_ops is still have some issues with memory limits, but any
>>>>>> new kernel (3.0+) will boot normal and operates with very
>>>>>> minor glitches. Older pv_ops (f.e. debian 2.6.32) have some
>>>>>> more major issues.
>>>>> what glitches should one expect with 3.0+, and having the choice,
>>>>> would it be better to go with 3.1 or even 3.2?
>>>> Right now I know about two of them:
>>>> When you set up memory for virtual machine using xenballon, value in
>>>> dom0 differ from value in domU. The issue is that -xen kernels 'hide'
>>>> some memory in 'used' memory, and pv-ops just reducing TotalMem to value
>>>> without that memory. Practically that means if you set up memory for
>>>> domain to 2GiB client will saw only 1.95GiB and so on.
>>> This really makes no practical difference.  The memory is "used" is
>>> either case and the different reporting is a side-effect of the change
>>> in how certain memory allocations are done.
> 
> David,
> 
> You are thinking that this is the vmalloc vs kmalloc memory for the
> frontends?

That wasn't what I was thinking.  When I looked (not very hard) at this
in dom0 I thought most of it was the swiotlb buffer.

David