Simplify reconnection protocol of GTM-Proxy to GTM

With this commit, reconnection of a GTM-Proxy to a GTM instance
is controlled only with the interval time between 2 reconnections.
While being in reconnection waiting process, it is possible to
specify new GTM connection information with gtm_ctl reconnect.

In consequence, 5 setting parameters of GTM-Proxy are removed here:
- err_wait_count
- err_wait_interval
- err_wait_idle
- gtm_connect_retry_count
- gtm_connect_retry_idle
Related information and documentation also is removed.

5 files changed, 36 insertions, 225 deletions

diff --git a/src/gtm/proxy/gtm_proxy.conf.sample b/src/gtm/proxy/gtm_proxy.conf.sample
index 3b275a43e6..b29c4dea57 100644
--- a/src/gtm/proxy/gtm_proxy.conf.sample
+++ b/src/gtm/proxy/gtm_proxy.conf.sample
@@ -53,19 +53,8 @@
 #------------------------------------------------------------------------------
 # Behavior at GTM communication error
 #------------------------------------------------------------------------------
-#gtm_connect_retry_idle = 0		# How long (in secs) to wait before GTM proxy
-			   					# retries to connect to GTM.
-#gtm_connect_retry_count = 0	# How many times GTM proxy retries to connect
-								# to GTM.
 #gtm_connect_retry_interval = 0	# How long (in secs) to wait until the next
 								# retry to connect to GTM.
-#err_wait_idle = 0				# How long (in secs) GTM proxy should wait
-			   	 				# before it detects reconnect from gtm_ctl.
-#err_wait_count = 0				# How many times GTM should detect reconnect
-								# from gtm_ctl.
-#err_wait_interval = 0			# How long (in secs) GTM proxy should wait
-								# until next detection of reconnect from
-								# gtm_ctl.
 #
 #
 #------------------------------------------------------------------------------
diff --git a/src/gtm/proxy/gtm_proxy_opt.c b/src/gtm/proxy/gtm_proxy_opt.c
index 7459e29de1..4ed7722f93 100644
--- a/src/gtm/proxy/gtm_proxy_opt.c
+++ b/src/gtm/proxy/gtm_proxy_opt.c
@@ -49,19 +49,8 @@ extern int tcp_keepalives_count;
 extern int tcp_keepalives_interval;
 extern char *GTMServerHost;
 extern int GTMProxyPortNumber;
-extern bool IsGTMConnectRetryRequired;
-extern int GTMConnectRetryIdle;
-extern int GTMConnectRetryCount;
 extern int GTMConnectRetryInterval;
 extern int GTMServerPortNumber;
-/*
-extern int GTMServerKeepalivesIdle;
-extern int GTMServerKeepalivesInterval;
-extern int GTMServerKeepalivesCount;
-*/
-extern int GTMErrorWaitIdle;
-extern int GTMErrorWaitInterval;
-extern int GTMErrorWaitCount;
 extern int GTMProxyWorkerThreads;
 extern char *GTMProxyDataDir;
 extern char *GTMProxyConfigFileName;
@@ -185,36 +174,13 @@ struct config_int ConfigureNamesInt[] =
 	},
 	{
 		{
-			GTM_OPTNAME_CONNECT_RETRY_COUNT, GTMC_SIGHUP,
-		 	gettext_noop("Retry count to try to reconnect to GTM."),
-		 	NULL,
-		 	0
-		},
-		&GTMConnectRetryCount,
-		0, 0, INT_MAX,
-		0, NULL
-	},
-	{
-		{
-			GTM_OPTNAME_CONNECT_RETRY_IDLE, GTMC_SIGHUP,
-		 	gettext_noop("Idle time in second before GTM standby retries "
-						 "connection to GTM."),
-		 	NULL,
-		 	GTMOPT_UNIT_TIME
-		},
-		&GTMConnectRetryIdle,
-		0, 0, INT_MAX,
-		0, NULL
-	},
-	{
-		{
 			GTM_OPTNAME_CONNECT_RETRY_INTERVAL, GTMC_SIGHUP,
 			gettext_noop("Interval in second to detect reconnect command."),
 			NULL,
 			GTMOPT_UNIT_TIME
 		},
 		&GTMConnectRetryInterval,
-		0, 0, INT_MAX,
+		60, 0, INT_MAX,
 		0, NULL
 	},
 	{
@@ -252,43 +218,6 @@ struct config_int ConfigureNamesInt[] =
 	},
 	{
 		{
-			GTM_OPTNAME_ERR_WAIT_IDLE, GTMC_SIGHUP,
-			gettext_noop("Time duration after connection to GTM failed and "
-						 "wait for reconnect command begins."),
-			gettext_noop("This parameter determines GTM Proxy behavior "
-						 "when GTM communication error is encountered."),
-			0
-		},
-		&GTMErrorWaitIdle,
-		0, 0, INT_MAX,
-		0, NULL
-	},
-	{
-		{
-			GTM_OPTNAME_ERR_WAIT_INTERVAL, GTMC_SIGHUP,
-			gettext_noop("Wait interval to wait for reconnect."),
-			gettext_noop("This parameter determines GTM Proxy behavior "
-						 "when GTM communication error is encountered."),
-			0
-		},
-		&GTMErrorWaitInterval,
-		0, 0, INT_MAX,
-		0, NULL
-	},
-	{
-		{
-			GTM_OPTNAME_ERR_WAIT_COUNT, GTMC_SIGHUP,
-			gettext_noop("Number of err_wait_interval to wait for reconnect."),
-			gettext_noop("This parameter determines GTM Prox behavior "
-						 "when GTM communication error is encountered."),
-		 0
-		},
-		&GTMErrorWaitCount,
-		0, 0, INT_MAX,
-		0, NULL
-	},
-	{
-		{
 			GTM_OPTNAME_WORKER_THREADS, GTMC_STARTUP,
 			gettext_noop("Number of worker thread."),
 			NULL,
diff --git a/src/gtm/proxy/proxy_main.c b/src/gtm/proxy/proxy_main.c
index 2cc78f7dfd..9de9d0c7a2 100644
--- a/src/gtm/proxy/proxy_main.c
+++ b/src/gtm/proxy/proxy_main.c
@@ -71,18 +71,10 @@ char		*GTMProxyDataDir;
 char		*GTMProxyConfigFileName;
 char		*GTMConfigFileName;
 
-/* GTM communication error handling options */
-int			GTMErrorWaitIdle = 0;
-int			GTMErrorWaitInterval = 0;		/* Duration of each wait */
-int			GTMErrorWaitCount = 0;			/* How many durations to wait */
-
 char		*GTMServerHost;
 int			GTMServerPortNumber;
 
-/* GTM connection retry info */
-int			GTMConnectRetryIdle = 0;
-int			GTMConnectRetryCount = 0;
-int			GTMConnectRetryInterval = 0;
+int			GTMConnectRetryInterval = 60;
 
 /*
  * Keepalives setup for the connection with GTM server
@@ -579,8 +571,6 @@ main(int argc, char *argv[])
 	char	*log_file = NULL;
 	char	*gtm_host = NULL;
 	char	*gtm_port = NULL;
-	char	*gtm_err_wait_secs = NULL;
-	char   	*gtm_err_wait_count = NULL;
 
 	isStartUp = true;
 
@@ -612,7 +602,7 @@ main(int argc, char *argv[])
 	/*
 	 * Parse the command like options and set variables
 	 */
-	while ((opt = getopt(argc, argv, "h:i:p:n:D:l:s:t:w:z:")) != -1)
+	while ((opt = getopt(argc, argv, "h:i:p:n:D:l:s:t:")) != -1)
 	{
 		switch (opt)
 		{
@@ -672,20 +662,6 @@ main(int argc, char *argv[])
 				gtm_port = strdup(optarg);
 				break;
 
-			case 'w':
-				/* Duration to wait at GTM communication error */
-				if (gtm_err_wait_secs)
-					free(gtm_err_wait_secs);
-				gtm_err_wait_secs = strdup(optarg);
-				break;
-
-			case 'z':
-				/* How many durations to wait */
-				if (gtm_err_wait_count)
-					free(gtm_err_wait_count);
-				gtm_err_wait_count = strdup(optarg);
-				break;
-
 			default:
 				write_stderr("Try \"%s --help\" for more information.\n",
 							 progname);
@@ -754,18 +730,6 @@ main(int argc, char *argv[])
 		free(gtm_port);
 		gtm_port = NULL;
 	}
-	if (gtm_err_wait_secs)
-	{
-		SetConfigOption(GTM_OPTNAME_ERR_WAIT_INTERVAL, gtm_err_wait_secs, GTMC_STARTUP, GTMC_S_OVERRIDE);
-		free(gtm_err_wait_secs);
-		gtm_err_wait_secs = NULL;
-	}
-	if (gtm_err_wait_count)
-	{
-		SetConfigOption(GTM_OPTNAME_ERR_WAIT_COUNT, gtm_err_wait_count, GTMC_STARTUP, GTMC_S_OVERRIDE);
-		free(gtm_err_wait_count);
-		gtm_err_wait_count = NULL;
-	}
 
 
 	/*
@@ -1157,13 +1121,6 @@ GTMProxy_ThreadMain(void *argp)
 
 	initStringInfo(&input_message);
 
-	/*
-	 * Set GTM communication error handling options.
-	 */
-	thrinfo->thr_gtm_conn->gtmErrorWaitIdle = GTMErrorWaitIdle;
-	thrinfo->thr_gtm_conn->gtmErrorWaitInterval = GTMErrorWaitInterval;
-	thrinfo->thr_gtm_conn->gtmErrorWaitCount = GTMErrorWaitCount;
-
 	thrinfo->reconnect_issued = FALSE;
 
 	/*
@@ -1665,100 +1622,51 @@ ProcessCommand(GTMProxy_ConnectionInfo *conninfo, GTM_Conn *gtm_conn,
 static GTM_Conn *
 HandleGTMError(GTM_Conn *gtm_conn)
 {
-	GTM_Conn *new_gtm_conn;
-	int		 ii;
-
 	Assert(gtm_conn && gtm_conn->last_errno != 0);
 
-	if (GTMConnectRetryCount > 0)
+	elog(NOTICE,
+		 "GTM communication error was detected.  Retrying connection, interval = %d.",
+		 GTMConnectRetryInterval);
+	for (;;)
 	{
-		int ii;
 		char gtm_connect_string[1024];
 
-		elog(NOTICE,
-			 "GTM communication error was detected.  Retrying connection. idle: %d, count = %d, interval = %d.",
-			 GTMConnectRetryIdle, GTMConnectRetryCount, GTMConnectRetryInterval);
+		/* Wait and retry reconnect */
+		elog(DEBUG1, "Waiting %d secs.", GTMConnectRetryInterval);
+		pg_usleep((long)GTMConnectRetryInterval * 1000000L);
+
+		/*
+		 * Connect retry
+		 * Because this proxy has been registered to current
+		 * GTM, we don't re-register it.
+		 *
+		 * Please note that GTM-Proxy accepts "reconnect" from gtm_ctl
+		 * even while it is retrying to connect to GTM.
+		 */
+		elog(DEBUG1, "Try to reconnect to GTM");
+		/* Make sure RECONNECT command would not come while we reconnecting */
+		Disable_Longjmp();
+		/* Close and free previous connection object if still active */
 		GTMPQfinish(gtm_conn);
+		/* Reconnect */
 		sprintf(gtm_connect_string, "host=%s port=%d node_name=%s remote_type=%d",
 				GTMServerHost, GTMServerPortNumber, GTMProxyNodeName, GTM_NODE_GTM_PROXY);
-		/* Wait and retry reconnect */
-		if (GTMConnectRetryIdle > 0) {
-			elog(DEBUG1, "Waiting %d secs.", GTMConnectRetryIdle);
-			pg_usleep((long)GTMConnectRetryIdle * 1000000L);
-		}
-		/* GTM connection retry */
-		for (ii = 0; ii < GTMConnectRetryCount; ii++)
-		{
-			/*
-			 * Connect retry
-			 * Because this proxy has been registered to current
-			 * GTM, we don't re-register it.
-			 *
-			 * Please note that GTM-Proxy accepts "reconnect" from gtm_ctl
-			 * even while it is retrying to connect to GTM.
-			 */
-			elog(DEBUG1, "Try to reconnect to GTM, count %d.", ii);
-			Disable_Longjmp();
-			new_gtm_conn = PQconnectGTM(gtm_connect_string);
-			Enable_Longjmp();
-			if (new_gtm_conn != NULL) {
-				elog(NOTICE, "GTM connection retry succeeded, count %d.", ii);
-				break;
-			}
-			/* Wait if not successful */
-			elog(DEBUG1, "Reconnect failed.  Sleeping %d secs.", GTMConnectRetryInterval);
-			Disable_Longjmp();
-			pg_usleep((long)GTMConnectRetryInterval * 1000000L);
-			Enable_Longjmp();
-		}
-		if (new_gtm_conn != NULL)
-		{
-			GetMyThreadInfo->thr_gtm_conn = new_gtm_conn;
-			return(new_gtm_conn);
-		}
-		elog(NOTICE, "GTM connection retry failed.");
-	}
-	if (GTMErrorWaitIdle == 0 && GTMErrorWaitInterval == 0 && GTMErrorWaitCount == 0)
-	{
+		gtm_conn = PQconnectGTM(gtm_connect_string);
 		/*
-		 * GTM communication error detected, retry failed
-		 * but cannot wait for reconnect.
+		 * If reconnect succeeded the connection will be ready to use out of
+		 * there, otherwise thr_gtm_conn will be set to NULL preventing double
+		 * free.
 		 */
-		elog(FATAL,
-			 "No action specified to wait for reconnect.");
-		exit(1);		/* Just in case */
-	}
-	/*
-	 * Now wait for reconnect, SIGUSR2.
-	 *
-	 * All the controls are done by Disable_Logjmp() and Enable_Longjmp().
-	 * No longjump occurs after Disable_longjmp() and before Enable_longjmp().
-	 * Longjmp occurs inside Enable_longjmp(), only when SIGUSR2 was handled
-	 * correctly.
-	 *
-	 * For details, see gtm_proxy.h.
-	 */
-	elog(NOTICE,
-		 "Waiting for reconnect action from gtm_ctl. idie: %d, count: %d, interval:%d",
-		 GTMErrorWaitIdle, GTMErrorWaitCount, GTMErrorWaitInterval);
-	Disable_Longjmp();
-	elog(DEBUG1, "Witing %d secs.", GTMErrorWaitIdle);
-	pg_usleep((long)GTMErrorWaitIdle * 1000000L);
-	Enable_Longjmp();
-
-	for (ii = 0; ii < GTMErrorWaitCount; ii++)
-	{
-		Disable_Longjmp();
-		elog(DEBUG1, "Waiting %d secs, count %d.", GTMErrorWaitInterval, ii);
-		pg_usleep((long)GTMErrorWaitInterval * 1000000L);
+		GetMyThreadInfo->thr_gtm_conn = gtm_conn;
 		Enable_Longjmp();
+		if (gtm_conn)
+		{
+			/* Success, update thread info and return new connection */
+			elog(NOTICE, "GTM connection retry succeeded.");
+			return gtm_conn;
+		}
+		elog(NOTICE, "GTM connection retry failed.");
 	}
-	/*
-	 * No reconnect received.
-	 */
-	elog(FATAL,
-		 "No reconnect command recdeived frm gtm_ctl.");
-	exit(1);		/* Just in case */
 }
 
 static GTM_Conn *
@@ -3387,11 +3295,6 @@ workerThreadReconnectToGTM(void)
 		elog(FATAL, "Worker thread GTM connection failed.");
 	elog(LOG, "Worker thread connection done.");
 
-	/* Set GTM communication error handling option */
-	GetMyThreadInfo->thr_gtm_conn->gtmErrorWaitIdle = GTMErrorWaitIdle;
-	GetMyThreadInfo->thr_gtm_conn->gtmErrorWaitInterval = GTMErrorWaitInterval;
-	GetMyThreadInfo->thr_gtm_conn->gtmErrorWaitCount = GTMErrorWaitCount;
-
 	/* Initialize the command processing */
 	GetMyThreadInfo->reconnect_issued = FALSE;
 }
diff --git a/src/include/gtm/gtm_opt.h b/src/include/gtm/gtm_opt.h
index 6d33782055..3701d1c469 100644
--- a/src/include/gtm/gtm_opt.h
+++ b/src/include/gtm/gtm_opt.h
@@ -332,12 +332,7 @@ const char *const config_type_names[] =\
 #define GTM_OPTNAME_ACTIVE_PORT 		"active_port"
 #define GTM_OPTNAME_CONFIG_FILE			"config_file"
 #define GTM_OPTNAME_DATA_DIR			"data_dir"
-#define GTM_OPTNAME_ERR_WAIT_COUNT		"err_wait_count"
-#define GTM_OPTNAME_ERR_WAIT_INTERVAL	"err_wait_interval"
-#define GTM_OPTNAME_ERR_WAIT_IDLE		"err_wait_idle"
 #define GTM_OPTNAME_ERROR_REPORTER		"error_reporter"
-#define GTM_OPTNAME_CONNECT_RETRY_COUNT "gtm_connect_retry_count"
-#define GTM_OPTNAME_CONNECT_RETRY_IDLE  "gtm_connect_retry_idle"
 #define GTM_OPTNAME_CONNECT_RETRY_INTERVAL "gtm_connect_retry_interval"
 #define GTM_OPTNAME_GTM_HOST			"gtm_host"
 #define GTM_OPTNAME_GTM_PORT			"gtm_port"
diff --git a/src/include/gtm/libpq-int.h b/src/include/gtm/libpq-int.h
index 0861560a61..692bf201dc 100644
--- a/src/include/gtm/libpq-int.h
+++ b/src/include/gtm/libpq-int.h
@@ -90,11 +90,6 @@ struct gtm_conn
 	/* Buffer for receiving various parts of messages */
 	PQExpBufferData	workBuffer; /* expansible string */
 
-	/* Options to handle GTM communication error */
-	int		gtmErrorWaitIdle;		/* If true, wait reconnect signal. */
-	int		gtmErrorWaitInterval;	/* Duration of the wait time in second */
-	int		gtmErrorWaitCount;		/* How many durations to wait */
-
 	/* Pointer to the result of last operation */
 	GTM_Result	*result;
 };