From 746812e67bddf513c61b6bac35aa2f3b087d6aaa Mon Sep 17 00:00:00 2001
From: Marko Kreen <markokr@gmail.com>
Date: Mon, 19 Jul 2010 07:30:15 +0000
Subject: [PATCH] Apply fast-fail at connect time.

If server is failing, the clients get error when connecting.
---
 include/objects.h |  1 +
 src/client.c      |  2 +-
 src/objects.c     | 57 +++++++++++++++++++++++++++++++++++--------------------
 3 files changed, 38 insertions(+), 22 deletions(-)

diff --git a/include/objects.h b/include/objects.h
index 3e2e6e9..25e1420 100644
--- a/include/objects.h
+++ b/include/objects.h
@@ -35,6 +35,7 @@ PgPool *get_pool(PgDatabase *, PgUser *);
 bool find_server(PgSocket *client)		_MUSTCHECK;
 bool release_server(PgSocket *server)		/* _MUSTCHECK */;
 bool finish_client_login(PgSocket *client)	_MUSTCHECK;
+bool check_fast_fail(PgSocket *client)		_MUSTCHECK;
 
 PgSocket * accept_client(int sock, const struct sockaddr_in *addr, bool is_unix) _MUSTCHECK;
 void disconnect_server(PgSocket *server, bool notify, const char *reason, ...) _PRINTF(3, 4);
diff --git a/src/client.c b/src/client.c
index cc6c416..e43ee12 100644
--- a/src/client.c
+++ b/src/client.c
@@ -97,7 +97,7 @@ bool set_pool(PgSocket *client, const char *dbname, const char *username)
 		return false;
 	}
 
-	return true;
+	return check_fast_fail(client);
 }
 
 static bool decide_startup_pool(PgSocket *client, PktHdr *pkt)
diff --git a/src/objects.c b/src/objects.c
index 07ad1cb..a391d5e 100644
--- a/src/objects.c
+++ b/src/objects.c
@@ -481,6 +481,39 @@ void activate_client(PgSocket *client)
 	sbuf_continue(&client->sbuf);
 }
 
+/*
+ * Don't let clients queue at all, if there is no working server connection.
+ *
+ * It must still allow following cases:
+ * - empty pool on startup
+ * - idle pool where all servers are removed
+ *
+ * Current assumptions:
+ * - old server connections will be dropped by query_timeout
+ * - new server connections fail due to server_connect_timeout, or other failure
+ *
+ * So here we drop client if all server connections have been dropped
+ * and new one's fail.
+ */
+bool check_fast_fail(PgSocket *client)
+{
+	int cnt;
+	PgPool *pool = client->pool;
+
+	/* reject if no servers and last connect failed */
+	if (!pool->last_connect_failed)
+		return true;
+	cnt = pool_server_count(pool) - statlist_count(&pool->new_server_list);
+	if (cnt)
+		return true;
+	disconnect_client(client, true, "no working server connection");
+
+	/* usual relaunch wont work, as there are no waiting clients */
+	launch_new_connection(pool);
+
+	return false;
+}
+
 /* link if found, otherwise put into wait queue */
 bool find_server(PgSocket *client)
 {
@@ -510,27 +543,9 @@ bool find_server(PgSocket *client)
 				break;
 		}
 
-		/*
-		 * Don't let clients queue at all, if there is no working server connection.
-		 *
-		 * It must still allow following cases:
-		 * - empty pool on startup
-		 * - idle pool where all servers are removed
-		 *
-		 * Current logic:
-		 * - old server connections will be dropped by query_timeout
-		 * - new server connections fail due to server_connect_timeout, or other failure
-		 */
-		if (!server && pool->last_connect_failed) {
-			int cnt = pool_server_count(pool) - statlist_count(&pool->new_server_list);
-			if (!cnt) {
-				/* usual relaunch wont work, as there are no waiting clients */
-				launch_new_connection(client->pool);
-
-				disconnect_client(client, true, "no working server connection");
-				return false;
-			}
-		}
+		if (!server && !check_fast_fail(client))
+			return false;
+
 	}
 	Assert(!server || server->state == SV_IDLE);
 
-- 
2.11.4.GIT