On 5/12/21 9:01 AM, Jim Mattson wrote:
On Tue, May 11, 2021 at 7:37 PM Krish Sadhukhan
<krish.sadhukhan@xxxxxxxxxx> wrote:
Add the following per-VCPU statistic to KVM debugfs to show if a given
VCPU is running a nested guest:
nested_guest_running
Also add this as a per-VM statistic to KVM debugfs to show the total number
of VCPUs running a nested guest in a given VM.
Signed-off-by: Krish Sadhukhan <Krish.Sadhukhan@xxxxxxxxxx>
This is fine, but I don't really see its usefulness. OTOH, one
Two potential uses:
1. If Live Migration of L2 guests is broken/buggy, this can be used
to determine a safer time to trigger Live Migration of L1 guests.
2. This can be used to create a time-graph of the load of L1 and L2
in a given VM as well across the host.
statistic I would really like to see is how many vCPUs have *ever* run
a nested guest.
'nested_runs' statistic provides this data, though only till VCPUs are
alive. We can convert 'nested_runs' to be persistent beyond VCPU
destruction.
But I am curious about the usage you are thinking of with this.
