Re: Slow I/O on USB media after commit f664a3cc17b7d0a2bc3b3ab96181e1029b0ec0e6

Andrea Vai
2019-11-07T18:59:58Z

[Sorry for the duplicate message, it didn't reach the lists due to
html formatting]
Il giorno gio 7 nov 2019 alle ore 08:54 Damien Le Moal
<Damien.LeMoal@wdc.com> ha scritto:
>
> On 2019/11/07 16:04, Andrea Vai wrote:
> > Il giorno mer, 06/11/2019 alle 22.13 +0000, Damien Le Moal ha scritto:
> >>
> >>
> >> Please simply try your write tests after doing this:
> >>
> >> echo mq-deadline > /sys/block/<name of your USB
> >> disk>/queue/scheduler
> >>
> >> And confirm that mq-deadline is selected with:
> >>
> >> cat /sys/block/<name of your USB disk>/queue/scheduler
> >> [mq-deadline] kyber bfq none
> >
> > ok, which kernel should I test with this: the fresh git cloned, or the
> > one just patched with Alan's patch, or doesn't matter which one?
>
> Probably all of them to see if there are any differences.

with both kernels, the output of
cat /sys/block/sdh/queue/schedule

already contains [mq-deadline]: is it correct to assume that the echo
command and the subsequent testing is useless? What to do now?

Thanks, and bye
Andrea