From: Eric Dumazet <eduma...@google.com>
TCA_FQ_LOW_RATE_THRESHOLD sch_fq attribute was added in linux-4.9
Tested:
lpaa5:/tmp# tc -qd add dev eth1 root fq
lpaa5:/tmp# tc -s qd sh dev eth1
qdisc fq 8003: root refcnt 5 limit 10000p flow_limit 1000p buckets 4096 \
orphan_mask 4095 bands 3 priomap 1 2 2 2 1 2 0 0 1 1 1 1 1 1 1 1 quantum 3648 \
initial_quantum 18240 low_rate_threshold 550Kbit refill_delay 40.0ms
Sent 62139 bytes 395 pkt (dropped 0, overlimits 0 requeues 0)
backlog 0b 0p requeues 0
116 flows (114 inactive, 0 throttled)
1 gc, 0 highprio, 0 throttled
lpaa5:/tmp# ./netperf -H lpaa6 -t TCP_RR -l10 -- -q 500000 -r 300,300 -o
P99_LATENCY
99th Percentile Latency Microseconds
7081
lpaa5:/tmp# tc qd replace dev eth1 root fq low_rate_threshold 10Mbit
lpaa5:/tmp# ./netperf -H lpaa6 -t TCP_RR -l10 -- -q 500000 -r 300,300 -o
P99_LATENCY
99th Percentile Latency Microseconds
858
Signed-off-by: Eric Dumazet <eduma...@google.com>
---
tc/q_fq.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/tc/q_fq.c b/tc/q_fq.c
index c9efbfc4..45b2ffd9 100644
--- a/tc/q_fq.c
+++ b/tc/q_fq.c
@@ -55,6 +55,7 @@ static void explain(void)
fprintf(stderr, " [ quantum BYTES ] [ initial_quantum
BYTES ]\n");
fprintf(stderr, " [ maxrate RATE ] [ buckets NUMBER ]\n");
fprintf(stderr, " [ [no]pacing ] [ refill_delay TIME ]\n");
+ fprintf(stderr, " [ low_rate_threshold RATE ]\n");
fprintf(stderr, " [ orphan_mask MASK]\n");
}
@@ -79,6 +80,7 @@ static int fq_parse_opt(struct qdisc_util *qu, int argc, char
**argv,
unsigned int initial_quantum;
unsigned int buckets = 0;
unsigned int maxrate;
+ unsigned int low_rate_threshold;
unsigned int defrate;
unsigned int refill_delay;
unsigned int orphan_mask;
@@ -90,6 +92,7 @@ static int fq_parse_opt(struct qdisc_util *qu, int argc, char
**argv,
bool set_defrate = false;
bool set_refill_delay = false;
bool set_orphan_mask = false;
+ bool set_low_rate_threshold = false;
int pacing = -1;
struct rtattr *tail;
@@ -121,6 +124,13 @@ static int fq_parse_opt(struct qdisc_util *qu, int argc,
char **argv,
return -1;
}
set_maxrate = true;
+ } else if (strcmp(*argv, "low_rate_threshold") == 0) {
+ NEXT_ARG();
+ if (get_rate(&low_rate_threshold, *argv)) {
+ fprintf(stderr, "Illegal
\"low_rate_threshold\"\n");
+ return -1;
+ }
+ set_low_rate_threshold = true;
} else if (strcmp(*argv, "defrate") == 0) {
NEXT_ARG();
if (get_rate(&defrate, *argv)) {
@@ -196,6 +206,9 @@ static int fq_parse_opt(struct qdisc_util *qu, int argc,
char **argv,
if (set_maxrate)
addattr_l(n, 1024, TCA_FQ_FLOW_MAX_RATE,
&maxrate, sizeof(maxrate));
+ if (set_low_rate_threshold)
+ addattr_l(n, 1024, TCA_FQ_LOW_RATE_THRESHOLD,
+ &low_rate_threshold, sizeof(low_rate_threshold));
if (set_defrate)
addattr_l(n, 1024, TCA_FQ_FLOW_DEFAULT_RATE,
&defrate, sizeof(defrate));
@@ -276,6 +289,13 @@ static int fq_print_opt(struct qdisc_util *qu, FILE *f,
struct rtattr *opt)
if (rate != 0)
fprintf(f, "defrate %s ", sprint_rate(rate, b1));
}
+ if (tb[TCA_FQ_LOW_RATE_THRESHOLD] &&
+ RTA_PAYLOAD(tb[TCA_FQ_LOW_RATE_THRESHOLD]) >= sizeof(__u32)) {
+ rate = rta_getattr_u32(tb[TCA_FQ_LOW_RATE_THRESHOLD]);
+
+ if (rate != 0)
+ fprintf(f, "low_rate_threshold %s ", sprint_rate(rate,
b1));
+ }
if (tb[TCA_FQ_FLOW_REFILL_DELAY] &&
RTA_PAYLOAD(tb[TCA_FQ_FLOW_REFILL_DELAY]) >= sizeof(__u32)) {
refill_delay = rta_getattr_u32(tb[TCA_FQ_FLOW_REFILL_DELAY]);
