Added replication consistency routines

Added replication consistency routines
This commit is contained in:
MassimilianoPinto 2014-06-23 12:56:01 +02:00
parent d42469c6cc
commit 51d47accf7

View File

@ -75,9 +75,12 @@ static void diagnostics(DCB *, void *);
static void setInterval(void *, unsigned long);
static void defaultId(void *, unsigned long);
static void replicationHeartbeat(void *, int);
static SERVER *getServerByNodeId(MONITOR_SERVERS *, int);
static bool mon_status_changed(MONITOR_SERVERS* mon_srv);
static bool mon_print_fail_status(MONITOR_SERVERS* mon_srv);
static SERVER *getServerByNodeId(MONITOR_SERVERS *, int);
static SERVER *getSlaveOfNodeId(MONITOR_SERVERS *, int);
static void set_master_heartbeat(MYSQL_MONITOR *handle, MONITOR_SERVERS *database);
static void set_slave_heartbeat(MYSQL_MONITOR *handle, MONITOR_SERVERS *database);
static MONITOR_OBJECT MyObject = { startMonitor, stopMonitor, registerServer, unregisterServer, defaultUser, diagnostics, setInterval, defaultId, replicationHeartbeat };
@ -856,3 +859,194 @@ getServerByNodeId(MONITOR_SERVERS *ptr, int node_id) {
return NULL;
}
/**
* Fetch a MySQL slave node from a node_id
*
* @param ptr The list of servers to monitor
* @param node_id The MySQL server_id to fetch
*/
static SERVER *getSlaveOfNodeId(MONITOR_SERVERS *ptr, int node_id) {
SERVER *current;
while (ptr)
{
current = ptr->server;
if (current->master_id == node_id) {
return current;
}
ptr = ptr->next;
}
return NULL;
}
static void set_master_heartbeat(MYSQL_MONITOR *handle, MONITOR_SERVERS *database) {
unsigned long id = handle->id;
time_t heartbeat;
time_t purge_time;
char heartbeat_insert_query[128]="";
char heartbeat_purge_query[128]="";
/* create the maxscale_schema database */
if (mysql_query(database->con, "CREATE DATABASE IF NOT EXISTS maxscale_schema")) {
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"[mysql_mon]: Error creating maxscale_schema database in Master server"
": %s", mysql_error(database->con))));
database->server->rlag = -1;
}
/* create repl_heartbeat table in maxscale_schema database */
if (mysql_query(database->con, "CREATE TABLE IF NOT EXISTS "
"maxscale_schema.replication_heartbeat "
"(maxscale_id INT NOT NULL, "
"master_server_id INT NOT NULL, "
"master_timestamp INT UNSIGNED NOT NULL, "
"PRIMARY KEY ( master_server_id, maxscale_id ) ) "
"ENGINE=MYISAM DEFAULT CHARSET=latin1")) {
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"[mysql_mon]: Error creating maxscale_schema.replication_heartbeat table in Master server"
": %s", mysql_error(database->con))));
database->server->rlag = -1;
}
/* auto purge old values after 48 hours*/
purge_time = time(0) - (3600 * 48);
sprintf(heartbeat_purge_query, "DELETE FROM maxscale_schema.replication_heartbeat WHERE master_timestamp < %lu", purge_time);
if (mysql_query(database->con, heartbeat_purge_query)) {
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"[mysql_mon]: Error deleting from maxscale_schema.replication_heartbeat table: [%s], %s",
heartbeat_purge_query,
mysql_error(database->con))));
}
heartbeat = time(0);
/* set node_ts for master as time(0) */
database->server->node_ts = heartbeat;
sprintf(heartbeat_insert_query, "UPDATE maxscale_schema.replication_heartbeat SET master_timestamp = %lu WHERE master_server_id = %i AND maxscale_id = %lu", heartbeat, handle->master->node_id, id);
/* Try to insert MaxScale timestamp into master */
if (mysql_query(database->con, heartbeat_insert_query)) {
database->server->rlag = -1;
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"[mysql_mon]: Error updating maxscale_schema.replication_heartbeat table: [%s], %s",
heartbeat_insert_query,
mysql_error(database->con))));
} else {
if (mysql_affected_rows(database->con) == 0) {
heartbeat = time(0);
sprintf(heartbeat_insert_query, "REPLACE INTO maxscale_schema.replication_heartbeat (master_server_id, maxscale_id, master_timestamp ) VALUES ( %i, %lu, %lu)", handle->master->node_id, id, heartbeat);
if (mysql_query(database->con, heartbeat_insert_query)) {
database->server->rlag = -1;
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"[mysql_mon]: Error inserting into maxscale_schema.replication_heartbeat table: [%s], %s",
heartbeat_insert_query,
mysql_error(database->con))));
} else {
/* Set replication lag to 0 for the master */
database->server->rlag = 0;
LOGIF(LD, (skygw_log_write_flush(
LOGFILE_DEBUG,
"[mysql_mon]: heartbeat table inserted data for %s:%i", database->server->name, database->server->port)));
}
} else {
/* Set replication lag as 0 for the master */
database->server->rlag = 0;
LOGIF(LD, (skygw_log_write_flush(
LOGFILE_DEBUG,
"[mysql_mon]: heartbeat table updated for %s:%i", database->server->name, database->server->port)));
}
}
}
static void set_slave_heartbeat(MYSQL_MONITOR *handle, MONITOR_SERVERS *database) {
unsigned long id = handle->id;
time_t heartbeat;
char select_heartbeat_query[256] = "";
MYSQL_ROW row;
MYSQL_RES *result;
int num_fields;
sprintf(select_heartbeat_query, "SELECT master_timestamp "
"FROM maxscale_schema.replication_heartbeat "
"WHERE maxscale_id = %lu AND master_server_id = %i",
id, handle->master->node_id);
/* if there is a master then send the query to the slave with master_id*/
if (handle->master !=NULL && (mysql_query(database->con, select_heartbeat_query) == 0
&& (result = mysql_store_result(database->con)) != NULL)) {
num_fields = mysql_num_fields(result);
while ((row = mysql_fetch_row(result))) {
int rlag = -1;
time_t slave_read;
heartbeat = time(0);
slave_read = strtoul(row[0], NULL, 10);
if ((errno == ERANGE && (slave_read == LONG_MAX || slave_read == LONG_MIN)) || (errno != 0 && slave_read == 0)) {
slave_read = 0;
}
if (slave_read) {
/* set the replication lag */
rlag = heartbeat - slave_read;
}
/* set this node_ts as master_timestamp read from replication_heartbeat table */
database->server->node_ts = slave_read;
if (rlag >= 0) {
/* store rlag only if greater than monitor sampling interval */
database->server->rlag = (rlag > (handle->interval / 1000)) ? rlag : 0;
} else {
database->server->rlag = -1;
}
LOGIF(LD, (skygw_log_write_flush(
LOGFILE_DEBUG,
"[mysql_mon]: replication heartbeat: "
"server %s:%i is %i seconds behind master",
database->server->name,
database->server->port,
database->server->rlag)));
}
mysql_free_result(result);
} else {
database->server->rlag = -1;
database->server->node_ts = 0;
if (handle->master->node_id < 0) {
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"[mysql_mon]: error: replication heartbeat: "
"master_server_id NOT available for %s:%i",
database->server->name,
database->server->port)));
} else {
LOGIF(LE, (skygw_log_write_flush(
LOGFILE_ERROR,
"[mysql_mon]: error: replication heartbeat: "
"failed selecting from hearthbeat table of %s:%i : [%s], %s",
database->server->name,
database->server->port,
select_heartbeat_query,
mysql_error(database->con))));
}
}
}