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: v1.3.15.8~8
X-Git-Url: http://www.kaiwu.me/postgresql/commit/?a=commitdiff_plain;h=121c80111c37ff291d04fde300d035dff313af57;p=haproxy.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 0b8756b8a..82de26037 100644
--- a/src/checks.c
+++ b/src/checks.c
@@ -164,7 +164,7 @@ 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);
 	}
@@ -229,7 +229,7 @@ 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);
 	}
@@ -280,7 +280,7 @@ 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);
 }
@@ -320,7 +320,7 @@ 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);
 }