[Bloat] Excessive throttling with fq

[Hans-Kristian Bakke]

I can add that this is without BBR, just plain old kernel 4.8 cubic.

On 26 January 2017 at 19:36, Hans-Kristian Bakke <hkbakke at gmail.com> wrote:

> Another day, another fq issue (or user error).
>
> I try to do the seeminlig simple task of downloading a single large file
> over local gigabit  LAN from a physical server running kernel 4.8 and
> sch_fq on intel server NICs.
>
> For some reason it wouldn't go past around 25 MB/s. After having replaced
> SSL with no SSL, replaced apache with nginx and verified that there is
> plenty of bandwith available between my client and the server I tried to
> change qdisc from fq to pfifo_fast. It instantly shot up to around the
> expected 85-90 MB/s. The same happened with fq_codel in place of fq.
>
> I then checked the statistics for fq and the throttled counter is
> increasing massively every second (eth0 and eth1 is LACPed using Linux
> bonding so both is seen here):
>
> qdisc fq 8007: root refcnt 2 limit 10000p flow_limit 100p buckets 1024
> orphan_mask 1023 quantum 3028 initial_quantum 15140 refill_delay 40.0ms
>  Sent 787131797 bytes 520082 pkt (dropped 15, overlimits 0 requeues 0)
>  backlog 98410b 65p requeues 0
>   15 flows (14 inactive, 1 throttled)
>   0 gc, 2 highprio, 259920 throttled, 15 flows_plimit
> qdisc fq 8008: root refcnt 2 limit 10000p flow_limit 100p buckets 1024
> orphan_mask 1023 quantum 3028 initial_quantum 15140 refill_delay 40.0ms
>  Sent 2533167 bytes 6731 pkt (dropped 0, overlimits 0 requeues 0)
>  backlog 0b 0p requeues 0
>   24 flows (24 inactive, 0 throttled)
>   0 gc, 2 highprio, 397 throttled
>
> Do you have any suggestions?
>
> Regards,
> Hans-Kristian
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.bufferbloat.net/pipermail/bloat/attachments/20170126/39628947/attachment-0002.html>