ioprio_get(2) outdated

ioprio_get(2) outdated

[Tycho Kirchner]

Hi,
please update ioprio_get(2) to the today more common Multi-Queue Block 
IO Queueing Mechanism (blk-mq). In particular:

> These system calls have an effect only when used in conjunction
> with an I/O scheduler that supports I/O priorities.  As at kernel
> 2.6.17 the only such scheduler is the Completely Fair Queuing
> (CFQ) I/O scheduler.

As far as I know BFQ is the only mq-iosched which supports (read-) 
priorities. See also [1]. The kernel Documentation/block/ioprio.txt is 
outdated as well, I guess I'll send an email there too.

Thanks and kind regards
Tycho Kirchner



[1]: https://www.kernel.org/doc/html/latest/block/bfq-iosched.html

Re: ioprio_get(2) outdated

[Alejandro Colomar (man-pages)]

Hi Tycho,

On 5/20/21 12:30 PM, Tycho Kirchner wrote:
> Hi,
> please update ioprio_get(2) to the today more common Multi-Queue Block 
> IO Queueing Mechanism (blk-mq). In particular:
> 
>> These system calls have an effect only when used in conjunction
>> with an I/O scheduler that supports I/O priorities.  As at kernel
>> 2.6.17 the only such scheduler is the Completely Fair Queuing
>> (CFQ) I/O scheduler.
> 
> As far as I know BFQ is the only mq-iosched which supports (read-) 
> priorities. See also [1]. The kernel Documentation/block/ioprio.txt is 
> outdated as well, I guess I'll send an email there too.
> 
> Thanks and kind regards
> Tycho Kirchner

Okay, I don't know much about it, so I'll CC Michael.

Thanks,

Alex

> 
> 
> 
> [1]: https://www.kernel.org/doc/html/latest/block/bfq-iosched.html


-- 
Alejandro Colomar
Linux man-pages comaintainer; https://www.kernel.org/doc/man-pages/
Senior SW Engineer; http://www.alejandro-colomar.es/