On 16/01/2023 18.28, Pierre Morel wrote:
On 1/13/23 17:58, Nina Schoetterl-Glausch wrote:
On Thu, 2023-01-05 at 15:53 +0100, Pierre Morel wrote:
S390 adds two new SMP levels, drawers and books to the CPU
topology.
The S390 CPU have specific toplogy features like dedication
and polarity to give to the guest indications on the host
vCPUs scheduling and help the guest take the best decisions
on the scheduling of threads on the vCPUs.
Let us provide the SMP properties with books and drawers levels
and S390 CPU with dedication and polarity,
Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx>
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...
PTF([01]) are no performance bottle neck and the number of CPU is likely to
be small, even a maximum of 248 is possible KVM warns above 16 CPU so the
loop for setting all CPU inside PTF interception is not very problematic I
think.
KVM warns if you try to use more than the number of physical CPUs that you
have, not at hard-coded 16 CPUs. So if you've got an LPAR with 248 CPUs,
it's perfectly fine to use also 248 CPUs for your guest.
Thomas
