Messages in this thread | | | From | "Li,Rongqing" <> | Subject | 答复: [PATCH] KVM: Consider SMT idle status when halt polling | Date | Thu, 22 Jul 2021 12:16:53 +0000 |
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> > > SMT siblings share caches and other hardware, halt polling will > > > degrade its sibling performance if its sibling is busy > > > > Do you have any real scenario benefits? As the polling nature, some > > cloud providers will configure to their preferred balance of cpu usage > > and performance, and other cloud providers for their NFV scenarios > > which are more sensitive to latency are vCPU and pCPU 1:1 pin,you > > destroy these setups. > > > > Wanpeng >
Run a copy (single thread) Unixbench, with or without a busy poll program in its SMT sibling, and Unixbench score can lower 1/3 with SMT busy polling program
Can this case show this issue?
-Li
> True, it benefits for our real scenario. > > this patch can lower our workload compute latency in our multiple cores VM > which vCPU and pCPU is 1:1 pin, and the workload with lots of computation and > networking packets. > > -Li
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