Re: [PATCH 9/9] sched/psi: add PSI_IRQ to track IRQ/SOFTIRQ pressure

Abel Wu
2022-07-22T03:31:09Z

Hi Chengming,

On 7/21/22 12:04 PM, Chengming Zhou Wrote:
> Now PSI already tracked workload pressure stall information for
> CPU, memory and IO. Apart from these, IRQ/SOFTIRQ could have
> obvious impact on some workload productivity, such as web service
> workload.
>
> When CONFIG_IRQ_TIME_ACCOUNTING, we can get IRQ/SOFTIRQ delta time
> from update_rq_clock_task(), in which we can record that delta
> to CPU curr task's cgroups as PSI_IRQ_FULL status.

The {soft,}irq affection should be equal to all the runnable tasks
on that cpu, not only rq->curr. Further I think irqstall is per-cpu
rather than per-cgroup.

Abel