[libvirt] Inconsistent behavior between x86_64 and ppc64 when creating guests with NUMA node placement

[Michael Turek]

Just realized that this is probably more suited for the users mailing 
list. Please disregard, I'll move it there.

On Fri 12 Sep 2014 03:00:06 PM EDT, Michael Turek wrote:
> Hello all,
>
> I was recently trying out NUMA placement for my guests on both x86_64
> and ppc64 machines. When booting a guest on the x86_64 machine, the
> following specs were valid (obviously, just notable excepts from the xml):
>
> <memory unit='KiB'>8388608</memory>
> <currentMemory unit='KiB'>8388608</currentMemory>
>  <vcpu placement='static'>4</vcpu>
> ...
>   <cpu>
>     <topology sockets='4' cores='1' threads='1'/>
>     <numa>
>       <cell cpus='0-2' memory='6144'/>
>       <cell cpus='3' memory='2048'/>
>     </numa>
>   </cpu>
>
> However, on ppc64 this causes the following error:
>
> error: Failed to create domain from sample_guest.xml
> error: internal error: early end of file from monitor: possible problem:
> 2014-09-11T18:44:25.502140Z qemu-system-ppc64: total memory for NUMA
> nodes (8388608) should equal RAM size (200000000)
>
> The 200000000 is actually 8192 MB in bytes and hexidecimal. This is
> apparently just an issue with the error message.
>
> The following specs work on ppc64:
>   <cpu>
>     <topology sockets='4' cores='1' threads='1'/>
>     <numa>
>       <cell cpus='0-2' memory='6291456'/>
>       <cell cpus='3' memory='2097152'/>
>     </numa>
>   </cpu>
>
> Note that the memory for each cell is 6144*1024 and 2048*1024
> respectively. The issue is that the memory size for each NUMA cell
> should be specified in KiB, not MB
> (http://libvirt.org/formatdomain.html#resPartition "|memory| specifies
> the node memory in kibibyte").
>
> In short, it seems that specifying NUMA cell memory in MB works on
> x86_64 but not on ppc64. Does anyone have any insight to what's
> causing this, or if I'm misunderstanding something? Any help is
> appreciated, thank you!
>
> Regards,
> Mike Turek
>
>
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