Re: [Xen-devel] [PATCH v4 17/21] libxl: disallow memory relocation when vNUMA is enabled

[Wei Liu <wei.liu2@xxxxxxxxxx>]

On Wed, Jan 28, 2015 at 04:41:11PM +0000, Ian Campbell wrote:
> On Fri, 2015-01-23 at 11:13 +0000, Wei Liu wrote:
> > Disallow memory relocation when vNUMA is enabled, because relocated
> > memory ends up off node. Further more, even if we dynamically expand
> > node coverage in hvmloader, low memory and high memory may reside
> > in different physical nodes, blindly relocating low memory to high
> > memory gives us a sub-optimal configuration.
> 
> What are the downsides of doing this? Less flexible PCI passthrough/MMIO
> hole sizing I think? Anything else?

Yes, PCI passthrough and MMIO hole size are affected, but not to the
degree that they are unusable.  Going forward like this doesn't make
thing worse than before I think.  Memory relocation is already disabled
if we're using QEMU upstream.

> 
> Does some user doc somewhere need this adding?
> 
> (and now I think of it, the PoD vs. vnuma one too).
> 

Maybe release note or xl manpage?

Wei.

> Ian.

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel