On Sat, Jan 28, 2017 at 03:03:02PM +0100, Michal Privoznik wrote:
On 13.12.2016 13:12, Jaroslav Safka wrote:
Hi, we would like to introduce 3 new elements source,access and allocation in memoryBacking element. For now it was made for numa topology.
<memoryBacking> <source type="file|anonymous"/> <access mode="shared|private"/> <allocation mode="immediate|ondemand"/> </memoryBacking>
If allocation is immediate then -mem-prealloc should be added to the qemu commanline. If source is file then -object memory-backend-file,id=mem,size=1024M,mem-path=*lib dir path* -numa node,memdev=mem Will be added to the qemu commandline
If access is shared then the "share=on" parameter will be added to the memory-backend-file e.g. -object memory-backend-file,id=mem,size=1024M,mem-path=/var/lib/libvirt/qemu,share=on
The access mode can be overriden by specifying token memAccess in numa cell.
The test cpu-numa-memshared was removed, because behaviour was changed and is not needed anymore
I beg to disagree. What if you don't have any <memoryBacking/>?
I like these patches, but I'm not certainly sure about: a) domain XML (in the past we used to require an ACK on schema change from one of the Dans)
What are you unsure about ? This XML is what I suggested in previous rounds of discussion.
b) the location for qemu to create its mmaped files (patch 3/3). cfg->libDir looks very suspicious.
Well we've got two possibilities - source=anonymous, should be using /dev/shm, similar to how we do huge pages. For source=file, we need a real filesystem. Something under /var/lib/libvirt is reasonable. Perhaps a dedicated dir is needed ? eg /var/lib/libvirt/ram in order to provide a point where the admin can mount a sufficiently large filesystem ? Or make it configurable in /etc/libvirt/qemu.conf Regards, Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://entangle-photo.org -o- http://search.cpan.org/~danberr/ :|