Re: [PATCH 0/5] KVM: Turn the vcpu array into an xarray

2021-11-16 Thread Marc Zyngier
On Tue, 16 Nov 2021 15:03:40 +, Paolo Bonzini wrote: > > On 11/5/21 20:20, Marc Zyngier wrote: > > The kvm structure is pretty large. A large portion of it is the vcpu > > array, which is 4kB on x86_64 and arm64 as they deal with 512 vcpu > > VMs. Of course, hardly anyone runs VMs this big, s

Re: [PATCH 0/5] KVM: Turn the vcpu array into an xarray

2021-11-16 Thread Paolo Bonzini
On 11/5/21 20:20, Marc Zyngier wrote: The kvm structure is pretty large. A large portion of it is the vcpu array, which is 4kB on x86_64 and arm64 as they deal with 512 vcpu VMs. Of course, hardly anyone runs VMs this big, so this is often a net waste of memory and cache locality. A possible app

Re: [PATCH 0/5] KVM: Turn the vcpu array into an xarray

2021-11-16 Thread Paolo Bonzini
On 11/16/21 15:13, Juergen Gross wrote: On 05.11.21 20:20, Marc Zyngier wrote: The kvm structure is pretty large. A large portion of it is the vcpu array, which is 4kB on x86_64 and arm64 as they deal with 512 vcpu VMs. Of course, hardly anyone runs VMs this big, so this is often a net waste of

[PATCH 0/5] KVM: Turn the vcpu array into an xarray

2021-11-05 Thread Marc Zyngier
The kvm structure is pretty large. A large portion of it is the vcpu array, which is 4kB on x86_64 and arm64 as they deal with 512 vcpu VMs. Of course, hardly anyone runs VMs this big, so this is often a net waste of memory and cache locality. A possible approach is to turn the fixed-size array in