Re: [libvirt] [Qemu-devel] high outage times for qemu virtio network links during live migration, trying to debug
On 01/26/2016 10:45 AM, Daniel P. Berrange wrote:
On Tue, Jan 26, 2016 at 10:41:12AM -0600, Chris Friesen wrote:
> My question is, why doesn't qemu continue processing virtio
packets while
> the dirty page scanning and memory transfer over the network is proceeding?
The qemuDomainMigratePrepareTunnel3Params() method is responsible for
starting the QEMU process on the target host. This should not normally
have any impact on host networking connectivity, since the CPUs on that
target QEMU wouldn't be running at that point. Perhaps the mere act of
starting QEMU and plugging the TAP dev into the network on the target
host causes some issue though ? eg are you using a bridge that is doing
STP or something like that.
Well, looks like your suspicions were correct. Our fast-path backend was
mistakenly sending out a GARP when the backend was initialized as part of
creating the qemu process on the target host. Oops.
Thanks for your help.
Chris