From: Yuchung Cheng <ych...@google.com>
Dump some new fields added to tcp_info in v4.10: tcpi_busy_time,
tcpi_rwnd_limited, tcpi_sndbuf_limited.
Example output for a flow busy for 110ms but never measurably limited by
receive window or send buffer:
busy:110ms
Example output for a flow usually limited by receive window:
busy:111ms rwnd_limited:101ms(91.0%)
Example output for a flow sometimes limited by send buffer:
busy:50ms sndbuf_limited:10ms(20.0%)
Signed-off-by: Yuchung Cheng <ych...@google.com>
Signed-off-by: Neal Cardwell <ncardw...@google.com>
Signed-off-by: Eric Dumazet <eduma...@google.com>
Signed-off-by: Soheil Hassas Yeganeh <soh...@google.com>
---
misc/ss.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/misc/ss.c b/misc/ss.c
index 18cfa93..392dbf7 100644
--- a/misc/ss.c
+++ b/misc/ss.c
@@ -784,6 +784,9 @@ struct tcpstat {
double rcv_rtt;
double min_rtt;
int rcv_space;
+ unsigned long long busy_time;
+ unsigned long long rwnd_limited;
+ unsigned long long sndbuf_limited;
bool has_ts_opt;
bool has_sack_opt;
bool has_ecn_opt;
@@ -1875,6 +1878,18 @@ static void tcp_stats_print(struct tcpstat *s)
if (s->app_limited)
printf(" app_limited");
+ if (s->busy_time) {
+ printf(" busy:%llums", s->busy_time / 1000);
+ if (s->rwnd_limited)
+ printf(" rwnd_limited:%llums(%.1f%%)",
+ s->rwnd_limited / 1000,
+ 100.0 * s->rwnd_limited / s->busy_time);
+ if (s->sndbuf_limited)
+ printf(" sndbuf_limited:%llums(%.1f%%)",
+ s->sndbuf_limited / 1000,
+ 100.0 * s->sndbuf_limited / s->busy_time);
+ }
+
if (s->unacked)
printf(" unacked:%u", s->unacked);
if (s->retrans || s->retrans_total)
@@ -2171,6 +2186,9 @@ static void tcp_show_info(const struct nlmsghdr *nlh,
struct inet_diag_msg *r,
s.min_rtt = (double) info->tcpi_min_rtt / 1000;
s.delivery_rate = info->tcpi_delivery_rate * 8.;
s.app_limited = info->tcpi_delivery_rate_app_limited;
+ s.busy_time = info->tcpi_busy_time;
+ s.rwnd_limited = info->tcpi_rwnd_limited;
+ s.sndbuf_limited = info->tcpi_sndbuf_limited;
tcp_stats_print(&s);
free(s.dctcp);
free(s.bbr_info);
--
2.8.0.rc3.226.g39d4020
