[aorth]

Interesting! From a related discussion in 2017 on the bbr-dev mailing list:

  BBR will run well with fq_codel only after linux-4.13 (not yet released)

  Before linux-4.13, BBR _needs_  fq packet scheduler.

  fq is not fq_codel.

See: https://groups.google.com/forum/#!topic/bbr-dev/4jL4ropdOV8