Re: [PATCH blktests v4 09/11] nvme{045,047}: Calculate IO size for random fio jobs

From: Daniel Wagner
Date: Thu Jun 01 2023 - 04:47:17 EST


Sorry for the late response, had to deal with a lot of high prio stuff...

On Fri, May 19, 2023 at 01:36:17AM +0000, Shinichiro Kawasaki wrote:
> On May 17, 2023 / 04:44, Chaitanya Kulkarni wrote:
> > On 5/11/23 07:09, Daniel Wagner wrote:
> > > _nvme_calc_run_io_size() returns the jobs size for _run_fio_rand_io()
> > > function. The jobs size is the size per job, thus we have to divide
> > > through the number of CPUs.
> >
> > sorry I didn't understand why we have to divide through number of
> > CPUs ? isn't tht will change the current job size of the test ?
> >
> > unless we are increasing somewhere which I missed it .
>
> This change reduces the I/O size per job, but it keeps the total I/O size
> regardless of the number of CPUs. This will keep test case runtime reasonable
> on systems with hundreds of CPUs.

Yes, indeed.

> As for the test case nvme/045, it tests re-authentication. I don't think it
> requires total I/O size proportional to number of CPUs. As for the test case
> nvme/047, it exercises different queue types (write queue and poll queue). Does
> it require total I/O size proportional to number of CPUs? Daniel is the test
> case author, and I guessed he is ok with the change.

Yes :)

Thanks for applying these patches!