Re: [PATCH v2] nvme/tcp: Add support to set the tcp worker cpu affinity

From: Ming Lei
Date: Mon Apr 17 2023 - 03:40:16 EST


On Thu, Apr 13, 2023 at 09:29:41PM +0800, Li Feng wrote:
> The default worker affinity policy is using all online cpus, e.g. from 0
> to N-1. However, some cpus are busy for other jobs, then the nvme-tcp will
> have a bad performance.

Can you explain in detail how nvme-tcp performs worse in this situation?

If some of CPUs are knows as busy, you can submit the nvme-tcp io jobs
on other non-busy CPUs via taskset, or scheduler is supposed to choose
proper CPUs for you. And usually nvme-tcp device should be saturated
with limited io depth or jobs/cpus.


Thanks,
Ming