From: Krzysztof Piotr Oledzki <ole@ans.pl>
Date: Thu, 29 Jan 2009 23:52:49 +0000 (+0100)
Subject: [CRITICAL] fix server state tracking: it was O(n!) instead of O(n)
X-Git-Tag: v1.3.16-rc1~48
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f39c71c98174e0691c048ed4935b045ea64f93e4;p=thirdparty%2Fhaproxy.git

[CRITICAL] fix server state tracking: it was O(n!) instead of O(n)

Using the wrong operator (&& instead of &) causes DOWN->UP
transition to take longer than it should and to produce a lot of
redundant logs. With typical "track" usage (1-6 tracking servers) it
shouldn't make a big difference but for heavily tracked servers
this bug leads to hang with 100% CPU usage and extremely big
log spam.
---

diff --git a/src/checks.c b/src/checks.c
index eb316cbb63..1acff0d840 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -161,7 +161,7 @@ static void set_server_down(struct server *s)
 
 		s->down_trans++;
 
-		if (s->state && SRV_CHECKED)
+		if (s->state & SRV_CHECKED)
 			for(srv = s->tracknext; srv; srv = srv->tracknext)
 				set_server_down(srv);
 	}
@@ -226,7 +226,7 @@ static void set_server_up(struct server *s) {
 		Warning("%s", trash);
 		send_log(s->proxy, LOG_NOTICE, "%s", trash);
 
-		if (s->state && SRV_CHECKED)
+		if (s->state & SRV_CHECKED)
 			for(srv = s->tracknext; srv; srv = srv->tracknext)
 				set_server_up(srv);
 	}
@@ -277,7 +277,7 @@ static void set_server_disabled(struct server *s) {
 	if (!s->proxy->srv_bck && !s->proxy->srv_act)
 		set_backend_down(s->proxy);
 
-	if (s->state && SRV_CHECKED)
+	if (s->state & SRV_CHECKED)
 		for(srv = s->tracknext; srv; srv = srv->tracknext)
 			set_server_disabled(srv);
 }
@@ -317,7 +317,7 @@ static void set_server_enabled(struct server *s) {
 	Warning("%s", trash);
 	send_log(s->proxy, LOG_NOTICE, "%s", trash);
 
-	if (s->state && SRV_CHECKED)
+	if (s->state & SRV_CHECKED)
 		for(srv = s->tracknext; srv; srv = srv->tracknext)
 			set_server_enabled(srv);
 }