FQ(8) Linux FQ(8) (NAME) tc-fq - (Fair Queue) (SYNOPSIS) tc qdisc ... fq [ limit PACKETS ] [ flow_limit PACKETS ] [ quantum BYTES ] [ initial_quantum BYTES ] [ maxrate RATE ] [ buckets NUMBER ] [ orphan_mask NUMBER ] [ pacing | nopacing ] [ ce_threshold TIME ] (DESCRIPTION) FQ ( Fair Queue) (classless packet scheduler) (locally generated traffic) . (pacing) . FQ TCP . <<>> (flow) . ( ) (packet hash) . SO_MAX_PACING_RATE setsockopt . . . EDT ( Earliest Departure Time) TCP skb . (dequeueing) (round-robin) . FIFO ( TC_PRIO_CONTROL) . FQ (non-work-conserving) . TCP (idle times) TCP . << >> (slow start after idle) BDP . (PARAMETERS) limit . (drop) . . 10000 . flow_limit . 100 . quantum (RR) . . MTU . initial_quantum . IW10 . MTU ( <<>>) . maxrate . (unlimited) . SO_MAX_PACING_RATE . buckets . (bucket) (red-black tree) . : 1024 . orphan_mask fq skb->hash . (DDOS) 1023 ( 1024 ). [no]pacing . (enabled) . ce_threshold ECN (Congestion Experienced) . DCTCP . (EXAMPLES) # tc qdisc add dev eth0 root fq ce_threshold 4ms # tc -s -d qdisc show dev eth0 qdisc fq 8001: dev eth0 root refcnt 2 limit 10000p flow_limit 100p buckets 1024 orphan_mask 1023 quantum 3028b initial_quantum 15140b low_rate_threshold 550Kbit refill_delay 40.0ms ce_threshold 4.0ms Sent 72149092 bytes 48062 pkt (dropped 2176, overlimits 0 requeues 0) backlog 1937920b 1280p requeues 0 flows 34 (inactive 17 throttled 0) gc 0 highprio 0 throttled 0 ce_mark 47622 flows_plimit 2176 (SEE ALSO) tc(8), socket(7) (AUTHORS) FQ Eric Dumazet . iproute2 10 Sept 2015 FQ(8)