From: Amaury Denoyelle <adenoyelle@haproxy.com>
Date: Wed, 20 Oct 2021 13:04:03 +0000 (+0200)
Subject: MINOR: backend: improve perf with tcp proxies skipping idle conns
X-Git-Tag: v2.5-dev11~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=926712ab2d04b2c9a0658e0f9fc390be303baffd;p=thirdparty%2Fhaproxy.git

MINOR: backend: improve perf with tcp proxies skipping idle conns

Skip the hash connection calcul when reuse must not be used in
connect_server() : this is the case for TCP proxies. This should result
in slightly better performance when using this use-case.
---

diff --git a/src/backend.c b/src/backend.c
index 6d77864db9..ee55e45497 100644
--- a/src/backend.c
+++ b/src/backend.c
@@ -1269,48 +1269,55 @@ int connect_server(struct stream *s)
 	 * it can be NULL for dispatch mode or transparent backend */
 	srv = objt_server(s->target);
 
-	/* first, set unique connection parameters and then calculate hash */
-	memset(&hash_params, 0, sizeof(hash_params));
+	if (!(s->flags & SF_ADDR_SET)) {
+		err = alloc_dst_address(&s->target_addr, srv, s);
+		if (err != SRV_STATUS_OK)
+			return SF_ERR_INTERNAL;
 
-	/* 1. target */
-	hash_params.target = s->target;
+		s->flags |= SF_ADDR_SET;
+	}
+
+	err = alloc_bind_address(&bind_addr, srv, s);
+	if (err != SRV_STATUS_OK)
+		return SF_ERR_INTERNAL;
 
 #ifdef USE_OPENSSL
-	/* 2. sni */
 	if (srv && srv->ssl_ctx.sni) {
 		sni_smp = sample_fetch_as_type(s->be, s->sess, s,
 		                               SMP_OPT_DIR_REQ | SMP_OPT_FINAL,
 		                               srv->ssl_ctx.sni, SMP_T_STR);
+	}
+#endif
 
-		/* only test if the sample is not null as smp_make_safe (called
-		 * before ssl_sock_set_servername) can only fails if this is
-		 * not the case
-		 */
-		if (sni_smp) {
-			hash_params.sni_prehash =
-			  conn_hash_prehash(sni_smp->data.u.str.area,
-			                    sni_smp->data.u.str.data);
-		}
+	/* do not reuse if mode is not http */
+	if (!IS_HTX_STRM(s)) {
+		DBG_TRACE_STATE("skip idle connections reuse: no htx", STRM_EV_STRM_PROC|STRM_EV_SI_ST, s);
+		goto skip_reuse;
 	}
-#endif /* USE_OPENSSL */
 
-	/* 3. destination address */
-	if (!(s->flags & SF_ADDR_SET)) {
-		err = alloc_dst_address(&s->target_addr, srv, s);
-		if (err != SRV_STATUS_OK)
-			return SF_ERR_INTERNAL;
+	/* first, set unique connection parameters and then calculate hash */
+	memset(&hash_params, 0, sizeof(hash_params));
 
-		s->flags |= SF_ADDR_SET;
+	/* 1. target */
+	hash_params.target = s->target;
+
+#ifdef USE_OPENSSL
+	/* 2. sni
+	 * only test if the sample is not null as smp_make_safe (called before
+	 * ssl_sock_set_servername) can only fails if this is not the case
+	 */
+	if (sni_smp) {
+		hash_params.sni_prehash =
+		  conn_hash_prehash(sni_smp->data.u.str.area,
+		                    sni_smp->data.u.str.data);
 	}
+#endif /* USE_OPENSSL */
 
+	/* 3. destination address */
 	if (srv && (!is_addr(&srv->addr) || srv->flags & SRV_F_MAPPORTS))
 		hash_params.dst_addr = s->target_addr;
 
 	/* 4. source address */
-	err = alloc_bind_address(&bind_addr, srv, s);
-	if (err != SRV_STATUS_OK)
-		return SF_ERR_INTERNAL;
-
 	hash_params.src_addr = bind_addr;
 
 	/* 5. proxy protocol */
@@ -1324,12 +1331,6 @@ int connect_server(struct stream *s)
 
 	hash = conn_calculate_hash(&hash_params);
 
-	/* do not reuse if mode is not http */
-	if (!IS_HTX_STRM(s)) {
-		DBG_TRACE_STATE("skip idle connections reuse: no htx", STRM_EV_STRM_PROC|STRM_EV_SI_ST, s);
-		goto skip_reuse;
-	}
-
 	/* first, search for a matching connection in the session's idle conns */
 	srv_conn = session_get_conn(s->sess, s->target, hash);
 	if (srv_conn) {