Re: [PATCH 2/2] powerpc/kvm: Limit MAX_VCPUS for guests running on RT Linux

2015-02-23 Thread Scott Wood
On Fri, 2015-02-20 at 14:45 +0100, Alexander Graf wrote: > > On 18.02.15 10:32, Bogdan Purcareata wrote: > > Due to the introduction of the raw_spinlock for the KVM openpic, guests > > with a > > high number of VCPUs may induce great latencies on the underlying RT Linux > > system (e.g. cyclictes

Re: [PATCH 2/2] powerpc/kvm: Limit MAX_VCPUS for guests running on RT Linux

2015-02-20 Thread Alexander Graf
On 18.02.15 10:32, Bogdan Purcareata wrote: > Due to the introduction of the raw_spinlock for the KVM openpic, guests with a > high number of VCPUs may induce great latencies on the underlying RT Linux > system (e.g. cyclictest reports latencies of ~15ms for guests with 24 VCPUs). > This can be f

Re: [PATCH 2/2] powerpc/kvm: Limit MAX_VCPUS for guests running on RT Linux

2015-02-18 Thread Sebastian Andrzej Siewior
On 02/18/2015 10:32 AM, Bogdan Purcareata wrote: > Due to the introduction of the raw_spinlock for the KVM openpic, guests with a > high number of VCPUs may induce great latencies on the underlying RT Linux > system (e.g. cyclictest reports latencies of ~15ms for guests with 24 VCPUs). > This can b

[PATCH 2/2] powerpc/kvm: Limit MAX_VCPUS for guests running on RT Linux

2015-02-18 Thread Bogdan Purcareata
Due to the introduction of the raw_spinlock for the KVM openpic, guests with a high number of VCPUs may induce great latencies on the underlying RT Linux system (e.g. cyclictest reports latencies of ~15ms for guests with 24 VCPUs). This can be further aggravated by sending a lot of external interru