Re: [PATCH 5/5] qemu_validate.c: revert NUMA CPU range user warning
On 6/1/20 4:40 PM, Peter Krempa wrote:
On Mon, Jun 01, 2020 at 14:50:41 -0300, Daniel Henrique Barboza
wrote:
> Now that we have the auto-fill code in place, and with proper documentation
> to let the user know that (1) we will auto-fill the NUMA cpus up to the
> number to maximum VCPUs number if QEMU supports it and (2) the user
> is advised to always supply a complete NUMA topology, this warning
> is unneeded.
>
> This reverts commit 38d2e033686b5cc274f8f55075ce1985b71e329a.
Since we already have the validation in place for some time now I think
we should just keep it. The auto-filling would be a useful hack to work
around if config breaks, but judged by itself it's of questionable
benefit.
That's a good point. I agree that removing the message after being in place
for this long is more trouble than it's worth.
Specifically users might end up with a topology which they didn't
expect. Reasoning is basically the same as with qemu. Any default
behaviour here is a policy decision and it might not suit all uses.
An ideal situation would be QEMU to never accept incomplete NUMA topologies
in the first place.
Given that this wasn't the case and now there might be a plethora of guests
running with goofy topologies all around, the already existing warning
message + this auto-fill hack + documentation mentioning that users should
avoid these topologies is a fine solution from Libvirt side, in my
estimation.
Thanks,
DHB