Re: [PATCH] fs/proc: introduce /proc/stat2 file

[Davidlohr Bueso]

On Thu, 08 Nov 2018, Dave Chinner wrote:

> If only we had percpu counters that had a fixed, extremely low read
> overhead that doesn't care about the number of CPUs in the
> machine....
>
> Oh, wait, we do: percpu_counters.[ch].
>
> This all seems like a counter implementation deficiency to me, not
> an interface problem...

Yeah fair point, as long as we can sacrifice accuracy by replacing
kernel_stat -- or maybe just replace the hard irq stats, which I
still think only accounts for 1% of all stat users. I have not looked
at how filesystems tune the batch size, but it would certainly be worth
looking into methinks.

Thanks,
Davidlohr