On Tue, 28 Jun 2016, Cong Wang wrote: > > BTW, I've started to actually work on fixing this, and I've noticed that > > TBF behavior actually violates what's stated in pfifo_fast manpage: > > > > ========== > > Whenever an interface is created, the pfifo_fast qdisc is > > automatically used as a queue. If another qdisc is > > attached, it preempts the default pfifo_fast, which automatically > > returns to function when an existing qdisc is detached. > > > > In this sense this qdisc is magic, and unlike other qdiscs. > > ========== > > It is out of date, now default qdisc can be set to any other qdisc > via /proc. Also, probably due to historical reasons, we don't have > a unified default default qdisc, some uses bfifo, some uses pfifo, > we may break some existing script if we change that.
While I do understand that reasoning, I'd argue that unpredictable and unexpected behavior of TBF causing systems with non-working networking is much more likely than any userspace having hard dependency on the fact that default (*) qdisc for TBF is noop. (*) where 'default upon creation' != 'default when reset' Thanks, -- Jiri Kosina SUSE Labs
