Re: [PATCH v3 01/18] block: introduce duration-limits priority class

Martin K. Petersen
2023-01-31T02:58:49Z

Hi Bart!

> My understanding is that ionice uses the ioprio_set() system call and
> hence only affects foreground I/O but not page cache writeback. This
> is why I introduced the ioprio rq-qos policy (block/blk-ioprio.c). How
> about not adding CDL support in ioprio_set() and only supporting
> configuration of CDL via the v2 cgroup mechanism?

I suspect applications that care about CDL would probably not go through
the page cache. But I don't have a problem supporting cgroups at all.

Longer term, for the applications that I'm aware of that care about
this, we'd probably want to be able to specify things on a per-I/O basis
via io_uring, though.

--
Martin K. Petersen Oracle Linux Engineering