Re: [RFC] hw/nvme: Use irqfd to send interrupts

[Stefan Hajnoczi]

On Sun, Jul 24, 2022, 11:21 Jinhao Fan <fanjinhao21s@ict.ac.cn> wrote:

at 9:29 PM, Stefan Hajnoczi <stefanha@gmail.com> wrote:

>
> Nice, perf(1) is good for that. You can enable trace events and add
> kprobes/uprobes to record timestamps when specific functions are entered.
>

Thanks Stefan,

One last question: Currently we can achieve hundreds of KIOPS. That means
perf can easily capture millions of trace events per second. I found perf
has quite high overhead at such a rate of trace events. Do you have any
advices on tracing high IOPS tasks?

I don't. BTW uprobes are expensive but kprobes are cheaper.

Stefan