Re: Error Cannot acquire state change lock from remoteDispatchDomainMigratePrepare3Params during live migration of domains

I wonder if something is hitting the 'max_client_requests' limit and getting stalled. The initial thread message here says the lockup is happening during bulk concurrent live migrations of 200 VMs, 5 at a time. The default 'max_client_requests' is 5.... DANGER WILL ROBINSON... With live migration making requests across multiple libvirt daemons, if the target host has filled its 5 requests queue with long running operations, and then a "prepare migrate' call comes in, that'll get stalled behind a possibly slow operation at the RPC dispatch level. I'd suggest bumping 'max_client_requests' to 100 and seeing if the problem goes away. If so I wonder if we shouldn't raise our out of the box limits. '5' is pretty low considering the scale of virtualization hosts in the modern world, and where even my laptop has 20 CPUs and 64 GB of RAM.