On 2024/08/05 17:23, Michael S. Tsirkin wrote:
On Mon, Aug 05, 2024 at 04:53:52PM +0900, Akihiko Odaki wrote:
On 2024/08/05 16:30, Michael S. Tsirkin wrote:
On Sun, Aug 04, 2024 at 03:49:45PM +0900, Akihiko Odaki wrote:
I suggest disabling all offload features of virtio-net with 9.2.
Yea ... no.
I want to keep things consistent so I want to disable all at once. This change will be very uncomfortable for us, who are implementing offload features, but I hope it will motivate us to implement a proper solution.
It's uncomfortable for users.
An obvious alternative is to set cross-migrate=off by default (I dropped the no- prefix because no-cross-migrate=off is confusing). I don't have a particular idea whether cross-migrate should be on or off by default.
This is a trade-off of safety and performance. In general, I believe safety should come first before performance.
There's no actual safety issue here. You can't migrate certain configurations. So I don't really understand what "cross-migrate" is supposed to do: fail migration in 100% of cases?
"cross-migrate" means migration among hosts with different platforms (e.g., different kernels, vDPA devices). If cross-migrate=off, QEMU can still migrate on the same host (checkpoint and restart). QEMU can also migrate across hosts if the user ensures they are on the same platform.