[libvirt] Designing NVDIMM & memory-backend-file

[Richard W.M. Jones]

On Fri, Jul 01, 2016 at 04:35:18PM +0200, Michal Privoznik wrote:
[...]
> And while I'll be working on this, I want to take a look at NVDIMM
> feature that qemu introduced recently [2]. The way I understand it, it
> is very similar to my problem from above. The only difference (for the
> consistence) would be that the memory model would be something else than
> 'dimm' ('nvdimm' perhaps?)
> 
>     <memory model='nvdimm'>
>       <source>
>         <path>/tmp/nvdimm1</path>
>       </source>
>       <target>
>         <size unit='GiB'>10</size>
>       </target>
>     </memory>
> 
> 
> -machine pc,nvdimm -m 8G,maxmem=100G,slots=100 \
> -object memory-backend-file,id=mem1,share,mem-path=/tmp/nvdimm1,size=10G \
> -device nvdimm,memdev=mem1,id=nv1

This patch shows how libguestfs would like to construct the qemu
command line to enable DAX support:

https://www.redhat.com/archives/libguestfs/2016-May/msg00138.html

Note we need to control share (set share=off specifically).

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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