Re: xen/stable-2.6.32.x xen-4.1.1 live migration fails with kernels 2.6.39, 3.0.3 and 3.1-rc2

[Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>]

On Fri, Aug 26, 2011 at 07:26:29PM +0200, Andreas Olsowski wrote:
> >My todo list is not getting any shorter sadly so not sure when I will
> >get to try this out. But let me do that when I get my 32GB machine
> >working again.
> It would certainly be interesting to know if you experience the same
> thing on your platforms. This may or may not have sth to do with the
> hardware in play.

OK, got my box online.

Getting closer to trying to reproduce the problem.

> 
> 
> >
> >Yeah, that really points to either the tools not liking the
> >MFN being too high or the hypervisor. Or the save/resume path in the
> >Linux kernel is failing silently and sticking in invalid MFNs
> >as it can't deal with higher MFNs.
> >
> >In other words - need to run this to figure out.
> >
> >Unless you are up for helping out by debugging the code a bit and
> >seeing if you can come with a fix?
> 
> Allthough i am willing, i probably wont be able to, since i lack the
> neccessary understanding of the low level workings of Xen and i am
> not very experienced at debugging C code/programs.

OK.
> 
> 
> However i did some additional testing, this time with xen4.2 and
> things have gotten worse:

Yeah, xen-unstable past c/s 23379 is doing a lot of weird stuff for me.

> 
> The two servers involved do BOTH have 96GB ram and are both running
> the latest xen 4.2 but are of different hardware (R710 and R610):
> http://pastebin.com/AaSpWZdg
> 
> And this is happens when i throw a 32GB server (PE2950) in the mix:
> http://pastebin.com/7X8t022R
> 
> So with 4.2 there are still migration errors, but whats worse, now i
> cant migrate anything anywhere anymore when the platform is
> different.
> 
> Within the same platform everything works fine (2x R610):
> http://pastebin.com/ZWByjjY5
> 
> What is going on here?

<sigh> Development - and not all developers test everything in the
mix.