> Il giorno 15 set 2021, alle ore 15:15, Jan Kara <jack@xxxxxxx> ha scritto: > > On Tue 31-08-21 11:59:30, Michal Koutný wrote: >> Hello Paolo. >> >> On Fri, Aug 27, 2021 at 12:07:20PM +0200, Paolo Valente <paolo.valente@xxxxxxxxxx> wrote: >>> Before discussing your patches in detail, I need a little help on this >>> point. You state that the number of scheduler tags must be larger >>> than the number of device tags. So, I expected some of your patches >>> to address somehow this issue, e.g., by increasing the number of >>> scheduler tags. Yet I have not found such a change. Did I miss >>> something? >> >> I believe Jan's conclusions so far are based on "manual" modifications >> of available scheduler tags by /sys/block/$dev/queue/nr_requests. >> Finding a good default value may be an additional change. > > Exactly. So far I was manually increasing nr_requests. I agree that > improving the default nr_requests value selection would be desirable as > well so that manual tuning is not needed. But for now I've left that aside. > Ok. So, IIUC, to recover control on bandwidth you need to (1) increase nr_requests manually and (2) apply your patch If you don't do (1), then (2) is not sufficient, and viceversa. Correct? Thanks, Paolo > Honza > -- > Jan Kara <jack@xxxxxxxx> > SUSE Labs, CR
