On Fri, Aug 11, 2017 at 4:16 PM, Stephen Hemminger <step...@networkplumber.org> wrote: > Any of the current qdisc that do rate control are single threaded. > Since bandwidth is a shared resource, the qdisc has to acquire a lock > and update cache shared data structures. > > Don't expect HTB or HFSC to be free. > This is a well known problem and there have been several attempts to address it over the years (a long time ago at Google I implemented a horrible hack called "hold queue" that put a parallelized queue in front of HTB. This eliminated the lock contention, but not without side effects).
Now there's a new scheduler proposed by some Googlers called Carousel that promises scalable host traffic shaping (https://www.cc.gatech.edu/~amsmti3/files/carousel-sigcomm17.pdf). Looks like they didn't implement a kernel Qdisc, but might be interesting for someone to look into... Tom >> >> 4.13-rc3 have kernel panic when deleting qdisc - will try to get panic trace > > Please do. >
