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Merge branch 'MAX-316' into develop

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This commit is contained in:
MassimilianoPinto
2014-11-07 17:02:56 +01:00
parent 00245201bb 39cc701b0d
commit 55d13ab46c
10 changed files with 202 additions and 38 deletions
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196
server/modules/monitor/galera_mon.c
View File

@ -30,6 +30,7 @@
* Interval is printed in diagnostics.
* 03/06/14 Mark Riddoch Add support for maintenance mode
* 24/06/14 Massimiliano Pinto Added depth level 0 for each node
* 30/10/14 Massimiliano Pinto Added disableMasterFailback feature
*
* @endverbatim
*/
@ -52,7 +53,7 @@ extern int lm_enabled_logfiles_bitmask;
static void monitorMain(void *);
static char *version_str = "V1.2.0";
static char *version_str = "V1.3.0";
MODULE_INFO info = {
MODULE_API_MONITOR,
@ -68,6 +69,9 @@ static void unregisterServer(void *, SERVER *);
static void defaultUsers(void *, char *, char *);
static void diagnostics(DCB *, void *);
static void setInterval(void *, size_t);
static MONITOR_SERVERS *get_candidate_master(MONITOR_SERVERS *);
static MONITOR_SERVERS *set_cluster_master(MONITOR_SERVERS *, MONITOR_SERVERS *, int);
static void disableMasterFailback(void *, int);
static MONITOR_OBJECT MyObject = {
startMonitor,
@ -80,7 +84,8 @@ static MONITOR_OBJECT MyObject = {
NULL,
NULL,
NULL,
NULL
NULL,
disableMasterFailback
};
/**
@ -148,6 +153,8 @@ MYSQL_MONITOR *handle;
handle->defaultPasswd = NULL;
handle->id = MONITOR_DEFAULT_ID;
handle->interval = MONITOR_INTERVAL;
handle->disableMasterFailback = 0;
handle->master = NULL;
spinlock_init(&handle->lock);
}
handle->tid = (THREAD)thread_start(monitorMain, handle);
@ -265,6 +272,7 @@ char *sep;
}
dcb_printf(dcb,"\tSampling interval:\t%lu milliseconds\n", handle->interval);
dcb_printf(dcb,"\tMaster Failback:\t%s\n", (handle->disableMasterFailback == 1) ? "off" : "on");
dcb_printf(dcb, "\tMonitored servers: ");
db = handle->databases;
@ -332,8 +340,10 @@ char *server_string;
char *dpwd = decryptPassword(passwd);
int rc;
int read_timeout = 1;
int connect_timeout = 2;
database->con = mysql_init(NULL);
rc = mysql_options(database->con, MYSQL_OPT_CONNECT_TIMEOUT, (void *)&connect_timeout);
rc = mysql_options(database->con, MYSQL_OPT_READ_TIMEOUT, (void *)&read_timeout);
if (mysql_real_connect(database->con, database->server->name,
@ -346,7 +356,15 @@ char *server_string;
database->server->name,
database->server->port,
mysql_error(database->con))));
server_clear_status(database->server, SERVER_RUNNING);
/* Also clear Joined, M/S and Stickiness bits */
server_clear_status(database->server, SERVER_JOINED);
server_clear_status(database->server, SERVER_SLAVE);
server_clear_status(database->server, SERVER_MASTER);
server_clear_status(database->server, SERVER_MASTER_STICKINESS);
if (mysql_errno(database->con) == ER_ACCESS_DENIED_ERROR)
{
server_set_status(database->server, SERVER_AUTH_ERROR);
@ -422,10 +440,11 @@ char *server_string;
static void
monitorMain(void *arg)
{
MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
MONITOR_SERVERS *ptr;
long master_id;
size_t nrounds = 0;
MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
MONITOR_SERVERS *ptr;
size_t nrounds = 0;
MONITOR_SERVERS *candidate_master = NULL;
int master_stickiness = handle->disableMasterFailback;
if (mysql_thread_init())
{
@ -454,39 +473,35 @@ size_t nrounds = 0;
* interval, then skip monitoring checks. Excluding the first
* round.
*/
if (nrounds != 0 &&
((nrounds*MON_BASE_INTERVAL_MS)%handle->interval) >=
MON_BASE_INTERVAL_MS)
if (nrounds != 0 && ((nrounds*MON_BASE_INTERVAL_MS)%handle->interval) >= MON_BASE_INTERVAL_MS)
{
nrounds += 1;
continue;
}
nrounds += 1;
master_id = -1;
ptr = handle->databases;
while (ptr)
{
unsigned int prev_status = ptr->server->status;
monitorDatabase(ptr, handle->defaultUser, handle->defaultPasswd);
/* set master_id to the lowest value of ptr->server->node_id */
/* clear bits for non member nodes */
if ( ! SERVER_IN_MAINT(ptr->server) && (ptr->server->node_id < 0 || ! SERVER_IS_JOINED(ptr->server))) {
ptr->server->depth = -1;
if ((! SERVER_IN_MAINT(ptr->server)) && ptr->server->node_id >= 0 && SERVER_IS_JOINED(ptr->server)) {
ptr->server->depth = 0;
if (ptr->server->node_id < master_id && master_id >= 0) {
master_id = ptr->server->node_id;
} else {
if (master_id < 0) {
master_id = ptr->server->node_id;
}
}
} else if (!SERVER_IN_MAINT(ptr->server)) {
/* clear M/S status */
server_clear_status(ptr->server, SERVER_SLAVE);
server_clear_status(ptr->server, SERVER_MASTER);
ptr->server->depth = -1;
/* clear master sticky status */
server_clear_status(ptr->server, SERVER_MASTER_STICKINESS);
}
/* Log server status change */
if (ptr->server->status != prev_status ||
SERVER_IS_DOWN(ptr->server))
{
@ -497,24 +512,50 @@ size_t nrounds = 0;
ptr->server->port,
STRSRVSTATUS(ptr->server))));
}
ptr = ptr->next;
}
/*
* Let's select a master server:
* it could be the candidate master following MIN(node_id) rule or
* the server that was master in the previous monitor polling cycle
* Decision depends on master_stickiness value set in configuration
*/
/* get the candidate master, followinf MIN(node_id) rule */
candidate_master = get_candidate_master(handle->databases);
/* Select the master, based on master_stickiness */
handle->master = set_cluster_master(handle->master, candidate_master, master_stickiness);
ptr = handle->databases;
/* this server loop sets Master and Slave roles */
while (ptr)
{
if ((! SERVER_IN_MAINT(ptr->server)) && ptr->server->node_id >= 0 && master_id >= 0) {
/* set the Master role */
if (SERVER_IS_JOINED(ptr->server) && (ptr->server->node_id == master_id)) {
server_set_status(ptr->server, SERVER_MASTER);
server_clear_status(ptr->server, SERVER_SLAVE);
} else if (SERVER_IS_JOINED(ptr->server) && (ptr->server->node_id > master_id)) {
while (ptr && handle->master) {
if (!SERVER_IS_JOINED(ptr->server) || SERVER_IN_MAINT(ptr->server)) {
ptr = ptr->next;
continue;
}
if (ptr != handle->master) {
/* set the Slave role */
server_set_status(ptr->server, SERVER_SLAVE);
server_clear_status(ptr->server, SERVER_MASTER);
}
server_set_status(ptr->server, SERVER_SLAVE);
server_clear_status(ptr->server, SERVER_MASTER);
/* clear master stickyness */
server_clear_status(ptr->server, SERVER_MASTER_STICKINESS);
} else {
/* set the Master role */
server_set_status(handle->master->server, SERVER_MASTER);
server_clear_status(handle->master->server, SERVER_SLAVE);
if (candidate_master && handle->master->server->node_id != candidate_master->server->node_id) {
/* set master stickyness */
server_set_status(handle->master->server, SERVER_MASTER_STICKINESS);
} else {
/* clear master stickyness */
server_clear_status(ptr->server, SERVER_MASTER_STICKINESS);
}
}
ptr = ptr->next;
@ -534,3 +575,90 @@ setInterval(void *arg, size_t interval)
MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
memcpy(&handle->interval, &interval, sizeof(unsigned long));
}
/**
* get candidate master from all nodes
*
* The current available rule: get the server with MIN(node_id)
* node_id comes from 'wsrep_local_index' variable
*
* @param servers The monitored servers list
* @return The candidate master on success, NULL on failure
*/
static MONITOR_SERVERS *get_candidate_master(MONITOR_SERVERS *servers) {
MONITOR_SERVERS *ptr = servers;
MONITOR_SERVERS *candidate_master = NULL;
long min_id = -1;
/* set min_id to the lowest value of ptr->server->node_id */
while(ptr) {
if ((! SERVER_IN_MAINT(ptr->server)) && ptr->server->node_id >= 0 && SERVER_IS_JOINED(ptr->server)) {
ptr->server->depth = 0;
if ((ptr->server->node_id < min_id) && min_id >= 0) {
min_id = ptr->server->node_id;
candidate_master = ptr;
} else {
if (min_id < 0) {
min_id = ptr->server->node_id;
candidate_master = ptr;
}
}
}
ptr = ptr->next;
}
return candidate_master;
}
/**
* set the master server in the cluster
*
* master could be the last one from previous monitor cycle Iis running) or
* the candidate master.
* The selection is based on the configuration option mapped to master_stickiness
* The candidate master may change over time due to
* 'wsrep_local_index' value change in the Galera Cluster
* Enabling master_stickiness will avoid master change unless a failure is spotted
*
* @param current_master Previous master server
* @param candidate_master The candidate master server accordingly to the selection rule
* @return The master node pointer (could be NULL)
*/
static MONITOR_SERVERS *set_cluster_master(MONITOR_SERVERS *current_master, MONITOR_SERVERS *candidate_master, int master_stickiness) {
/*
* if current master is not set or master_stickiness is not enable
* just return candidate_master.
*/
if (current_master == NULL || master_stickiness == 0) {
return candidate_master;
} else {
/*
* if current_master is still a cluster member use it
*
*/
if (SERVER_IS_JOINED(current_master->server) && (! SERVER_IN_MAINT(current_master->server))) {
return current_master;
} else
return candidate_master;
}
}
/**
* Disable/Enable the Master failback in a Galera Cluster.
*
* A restarted / rejoined node may get back the previous 'wsrep_local_index'
* from Cluster: if the value is the lowest in the cluster it will be selected as Master
* This will cause a Master change even if there is no failure.
* The option if set to 1 will avoid this situation, keeping the current Master (if running) available
*
* @param arg The handle allocated by startMonitor
* @param disable To disable it use 1, 0 keeps failback
*/
static void
disableMasterFailback(void *arg, int disable)
{
MYSQL_MONITOR *handle = (MYSQL_MONITOR *)arg;
memcpy(&handle->disableMasterFailback, &disable, sizeof(int));
}

3
server/modules/monitor/mm_mon.c
View File

@ -80,7 +80,8 @@ static MONITOR_OBJECT MyObject = {
NULL,
NULL,
NULL,
detectStaleMaster
detectStaleMaster,
NULL
};
/**

3
server/modules/monitor/mysql_mon.c
View File

@ -107,7 +107,8 @@ static MONITOR_OBJECT MyObject = {
NULL,
defaultId,
replicationHeartbeat,
detectStaleMaster
detectStaleMaster,
NULL
};
/**

1
server/modules/monitor/mysqlmon.h
View File

@ -65,6 +65,7 @@ typedef struct {
unsigned long id; /**< Monitor ID */
int replicationHeartbeat; /**< Monitor flag for MySQL replication heartbeat */
int detectStaleMaster; /**< Monitor flag for MySQL replication Stale Master detection */
int disableMasterFailback; /**< Monitor flag for Galera Cluster Master failback */
MONITOR_SERVERS *master; /**< Master server for MySQL Master/Slave replication */
MONITOR_SERVERS *databases; /**< Linked list of servers to monitor */
} MYSQL_MONITOR;

1
server/modules/monitor/ndbcluster_mon.c
View File

@ -74,6 +74,7 @@ static MONITOR_OBJECT MyObject = {
NULL,
NULL,
NULL,
NULL,
NULL
};