Re: [PATCH] powerpc/paravirt: Improve vcpu_is_preempted

2023-10-17 Thread Aboorva Devarajan
On Mon, 2023-10-09 at 10:47 +0530, Srikar Dronamraju wrote: Hi Srikar, Benchmarked this patch on baremetal POWER9 node by launching KVM to observe the improvements achieved in KVM with the patched kernel. Below, you can find the schbench latency result comparision. System was running on SMT4 mod

Re: [PATCH] powerpc/paravirt: Improve vcpu_is_preempted

2023-10-11 Thread Srikar Dronamraju
* Shrikanth Hegde [2023-10-11 14:33:34]: > On 10/9/23 10:47 AM, Srikar Dronamraju wrote: > > Hi Srikar. This is an interesting patch. > > > PowerVM Hypervisor dispatches on a whole core basis. In a shared LPAR, a > s/whole/big > > Can we mention that a big core consist of two small cores. and

Re: [PATCH] powerpc/paravirt: Improve vcpu_is_preempted

2023-10-11 Thread Shrikanth Hegde
On 10/9/23 10:47 AM, Srikar Dronamraju wrote: Hi Srikar. This is an interesting patch. > PowerVM Hypervisor dispatches on a whole core basis. In a shared LPAR, a s/whole/big Can we mention that a big core consist of two small cores. and w.r.t linux a core is at small core. Hence there is mi

[PATCH] powerpc/paravirt: Improve vcpu_is_preempted

2023-10-08 Thread Srikar Dronamraju
PowerVM Hypervisor dispatches on a whole core basis. In a shared LPAR, a CPU from a core that is preempted may have a larger latency. In such a scenario, its preferable to choose a different CPU to run. If one of the CPUs in the core is active, i.e neither CEDED nor preempted, then consider this C