Hi.
Here the first patch for feature request "New Balancing algorithm (Peak) EWMA
#1570"
regards
Alex
From e95bf6a4bf107fdc59696c4b4a4ef7b03133b813 Mon Sep 17 00:00:00 2001
From: Aleksandar Lazic <al-hapr...@none.at>
Date: Thu, 24 Feb 2022 02:56:21 +0100
Subject: [PATCH] MINOR: sample: Add srv_rtt server round trip time sample
This sample fetch get the server round trip time
Part of feature request #1570
---
doc/configuration.txt | 8 +++++++
reg-tests/sample_fetches/srv_rtt.vtc | 34 ++++++++++++++++++++++++++++
src/tcp_sample.c | 15 ++++++++++++
3 files changed, 57 insertions(+)
create mode 100644 reg-tests/sample_fetches/srv_rtt.vtc
diff --git a/doc/configuration.txt b/doc/configuration.txt
index 572c79d55..be6a811c8 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -18958,6 +18958,14 @@ srv_name : string
While it's almost only used with ACLs, it may be used for logging or
debugging. It can also be used in a tcp-check or an http-check ruleset.
+srv_rtt : integer
+ Returns the Round Trip Time (RTT) measured by the kernel for the server
+ connection. <unit> is facultative, by default the unit is milliseconds. <unit>
+ can be set to "ms" for milliseconds or "us" for microseconds. If the server
+ connection is not established, if the connection is not TCP or if the
+ operating system does not support TCP_INFO, for example Linux kernels before
+ 2.4, the sample fetch fails.
+
7.3.4. Fetching samples at Layer 5
----------------------------------
diff --git a/reg-tests/sample_fetches/srv_rtt.vtc b/reg-tests/sample_fetches/srv_rtt.vtc
new file mode 100644
index 000000000..c0ad0cbae
--- /dev/null
+++ b/reg-tests/sample_fetches/srv_rtt.vtc
@@ -0,0 +1,34 @@
+varnishtest "srv_rtt sample fetch Test"
+
+#REQUIRE_VERSION=2.6
+
+feature ignore_unknown_macro
+
+server s1 {
+ rxreq
+ txresp
+} -start
+
+
+haproxy h1 -conf {
+ defaults
+ mode http
+ timeout connect "${HAPROXY_TEST_TIMEOUT-5s}"
+ timeout client "${HAPROXY_TEST_TIMEOUT-5s}"
+ timeout server "${HAPROXY_TEST_TIMEOUT-5s}"
+
+ frontend fe
+ bind "fd@${fe}"
+ http-response set-header srv-rrt "%[srv_rtt]"
+ default_backend be
+
+ backend be
+ server srv1 ${s1_addr}:${s1_port}
+} -start
+
+client c1 -connect ${h1_fe_sock} {
+ txreq -url "/"
+ rxresp
+ expect resp.status == 200
+ expect resp.http.srv-rrt ~ "[0-9]+"
+} -run
diff --git a/src/tcp_sample.c b/src/tcp_sample.c
index 19edcd243..7b8b616cb 100644
--- a/src/tcp_sample.c
+++ b/src/tcp_sample.c
@@ -446,6 +446,20 @@ smp_fetch_fc_reordering(const struct arg *args, struct sample *smp, const char *
return 0;
return 1;
}
+
+/* get the mean rtt of a client connection */
+static int
+smp_fetch_srv_rtt(const struct arg *args, struct sample *smp, const char *kw, void *private)
+{
+ if (!get_tcp_info(args, smp, 1, 0))
+ return 0;
+
+ /* By default or if explicitly specified, convert rtt to ms */
+ if (!args || args[0].type == ARGT_STOP || args[0].data.sint == TIME_UNIT_MS)
+ smp->data.u.sint = (smp->data.u.sint + 500) / 1000;
+
+ return 1;
+}
#endif // linux || freebsd || netbsd
#endif // TCP_INFO
@@ -478,6 +492,7 @@ static struct sample_fetch_kw_list sample_fetch_keywords = {ILH, {
#ifdef TCP_INFO
{ "fc_rtt", smp_fetch_fc_rtt, ARG1(0,STR), val_fc_time_value, SMP_T_SINT, SMP_USE_L4CLI },
{ "fc_rttvar", smp_fetch_fc_rttvar, ARG1(0,STR), val_fc_time_value, SMP_T_SINT, SMP_USE_L4CLI },
+ { "srv_rtt", smp_fetch_srv_rtt, ARG1(0,STR), val_fc_time_value, SMP_T_SINT, SMP_USE_L4CLI },
#if defined(__linux__) || defined(__FreeBSD__) || defined(__NetBSD__)
{ "fc_unacked", smp_fetch_fc_unacked, ARG1(0,STR), var_fc_counter, SMP_T_SINT, SMP_USE_L4CLI },
{ "fc_sacked", smp_fetch_fc_sacked, ARG1(0,STR), var_fc_counter, SMP_T_SINT, SMP_USE_L4CLI },
--
2.25.1
