On 09/10/2014 05:00 PM, zhanghailiang wrote:
On 2014/9/9 11:05, Alexandre DERUMIER wrote:
Hello,
I was playing with pc-dimm hotplug, and I notice that balloning is
not working on
memory space of pc-dimm devices.
example:
qemu -m size=1024,slots=255,maxmem=15000M
#free -m : 1024M
-> qmp balloon 512M
#free -m : 512M
-> hotplug pc-dimm 1G:
#free -m : 1512M
(This is the same behavior if qemu is started with pc-dimm devices)
qemu 2.1
Guest kernel : 3.12.
Does it need a guest balloon module update ?
Regards,
Alexandre Derumier
Hi,
I noticed this fault also;-), this is a bug in qemu, And some work in
process...
Actually in QEMU the hotplugged memory(named hotplug-memory) is
distinguished
from the common memory(named pc.ram). When do balloon action, QEMU
wrongly
stats the ram_size.
I will send a patch series which also include other bug fix for the
memory hotplug.
Thanks,
zhanghailiang
Why does hotplugging use a different name?
This also affects RDMA live migration - we are explicitly looking up
"pc.ram" ram blocks and pinning them for memory registration with Linux.
- Michael
