On 5/31/22 16:52, Durrant, Paul wrote:
-----Original Message-----
From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Sent: 31 May 2022 15:44
To: Allister, Jack <jalliste@xxxxxxxxxx>
Cc: bp@xxxxxxxxx; diapop@xxxxxxxxxxxx; hpa@xxxxxxxxx; jmattson@xxxxxxxxxx; joro@xxxxxxxxxx;
kvm@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; metikaya@xxxxxxxxxxxx; mingo@xxxxxxxxxx;
pbonzini@xxxxxxxxxx; rkrcmar@xxxxxxxxxx; sean.j.christopherson@xxxxxxxxx; tglx@xxxxxxxxxxxxx;
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Subject: RE: [EXTERNAL]...\n
On Tue, May 31, 2022 at 02:02:36PM +0000, Jack Allister wrote:
The reasoning behind this is that you may want to run a guest at a
lower CPU frequency for the purposes of trying to match performance
parity between a host of an older CPU type to a newer faster one.
That's quite ludicrus. Also, then it should be the host enforcing the
cpufreq, not the guest.
I'll bite... What's ludicrous about wanting to run a guest at a lower CPU freq to minimize observable change in whatever workload it is running?
Well, the right API is cpufreq, there's no need to make it a KVM
functionality.
Paolo
