func (mt *Mysqld) createDbaConnection() (*mysql.Connection, error) {
params, err := dbconfigs.MysqlParams(mt.dbaParams)
if err != nil {
return nil, err
}
return mysql.Connect(params)
}
func (mysqld *Mysqld) StartReplicationCommands(status *proto.ReplicationStatus) ([]string, error) {
params, err := dbconfigs.MysqlParams(mysqld.replParams)
if err != nil {
return nil, err
}
return mysqld.flavor.StartReplicationCommands(¶ms, status)
}
// NewDBConnection returns a new DBConnection based on the ConnParams
// and will use the provided stats to collect timing.
func NewDBConnection(info *sqldb.ConnParams, mysqlStats *stats.Timings) (*DBConnection, error) {
params, err := dbconfigs.MysqlParams(info)
if err != nil {
return nil, err
}
c, err := sqldb.Connect(params)
return &DBConnection{c, mysqlStats}, err
}
func CreateGenericConnection(info *mysql.ConnectionParams) (*DBConnection, error) {
params, err := dbconfigs.MysqlParams(info)
if err != nil {
return nil, err
}
c, err := mysql.Connect(params)
return &DBConnection{c}, err
}
// Connect connects to a db server
func (dc *DBClient) Connect() error {
params, err := dbconfigs.MysqlParams(dc.dbConfig)
if err != nil {
return err
}
dc.dbConn, err = sqldb.Connect(params)
if err != nil {
return fmt.Errorf("error in connecting to mysql db, err %v", err)
}
return nil
}
// SetMasterCommands returns the commands to run to make the provided
// host / port the master.
func (mysqld *Mysqld) SetMasterCommands(masterHost string, masterPort int) ([]string, error) {
flavor, err := mysqld.flavor()
if err != nil {
return nil, fmt.Errorf("SetMasterCommands needs flavor: %v", err)
}
params, err := dbconfigs.MysqlParams(mysqld.replParams)
if err != nil {
return nil, err
}
return flavor.SetMasterCommands(¶ms, masterHost, masterPort, int(masterConnectRetry.Seconds()))
}
// StartReplicationCommands returns the commands used to start
// replication to the provided master using the provided starting
// position. The provided MasterConnectRetry will be ignored and
// replaced by the command line parameter.
func (mysqld *Mysqld) StartReplicationCommands(status *proto.ReplicationStatus) ([]string, error) {
flavor, err := mysqld.flavor()
if err != nil {
return nil, fmt.Errorf("StartReplicationCommands needs flavor: %v", err)
}
params, err := dbconfigs.MysqlParams(mysqld.replParams)
if err != nil {
return nil, err
}
status.MasterConnectRetry = int(masterConnectRetry.Seconds())
return flavor.StartReplicationCommands(¶ms, status)
}
// NewSlaveConnection creates a new slave connection to the mysqld instance.
// It uses a pools.IDPool to ensure that the server IDs used to connect are
// unique within this process. This is done with the assumptions that:
//
// 1) No other processes are making fake slave connections to our mysqld.
// 2) No real slave servers will have IDs in the range 1-N where N is the peak
// number of concurrent fake slave connections we will ever make.
func NewSlaveConnection(mysqld *Mysqld) (*SlaveConnection, error) {
params, err := dbconfigs.MysqlParams(mysqld.dba)
if err != nil {
return nil, err
}
conn, err := mysql.Connect(params)
if err != nil {
return nil, err
}
sc := &SlaveConnection{
Connection: conn,
mysqld: mysqld,
slaveID: slaveIDPool.Get(),
}
log.Infof("new slave connection: slaveID=%d", sc.slaveID)
return sc, nil
}
// connectForReplication create a MySQL connection ready to use for replication.
func (mysqld *Mysqld) connectForReplication() (sqldb.Conn, error) {
params, err := dbconfigs.MysqlParams(mysqld.dba)
if err != nil {
return nil, err
}
conn, err := sqldb.Connect(params)
if err != nil {
return nil, err
}
// Tell the server that we understand the format of events
// that will be used if binlog_checksum is enabled on the server.
if _, err := conn.ExecuteFetch("SET @master_binlog_checksum=@@global.binlog_checksum", 0, false); err != nil {
return nil, fmt.Errorf("failed to set @master_binlog_checksum=@@global.binlog_checksum: %v", err)
}
return conn, nil
}
// setupPrimerConnections creates the channel and the consumers for
// the sql statements
func (pc *PrimeCache) setupPrimerConnections() error {
pc.workerChannel = make(chan string, 1000)
for i := 0; i < pc.WorkerCount; i++ {
// connect to the database using client for a replay connection
params, err := dbconfigs.MysqlParams(&pc.dbcfgs.App.ConnectionParams)
if err != nil {
return fmt.Errorf("cannot get parameters to connect to MySQL: %v", err)
}
dbConn, err := mysql.Connect(params)
if err != nil {
return fmt.Errorf("mysql.Connect failed: %v", err)
}
// and launch the go routine that applies the statements
go applyLoop(dbConn, pc.workerChannel)
}
return nil
}
func StartReplicationCommands(mysqld *Mysqld, replState *proto.ReplicationState) ([]string, error) {
params, err := dbconfigs.MysqlParams(mysqld.replParams)
if err != nil {
return nil, err
}
nmd := &newMasterData{
ReplicationState: replState,
MasterUser: params.Uname,
MasterPassword: params.Pass,
}
cmc, err := fillStringTemplate(changeMasterCmd, nmd)
if err != nil {
return nil, err
}
if params.SslEnabled() {
cmc += ",\n MASTER_SSL = 1"
}
if params.SslCa != "" {
cmc += ",\n MASTER_SSL_CA = '" + params.SslCa + "'"
}
if params.SslCaPath != "" {
cmc += ",\n MASTER_SSL_CAPATH = '" + params.SslCaPath + "'"
}
if params.SslCert != "" {
cmc += ",\n MASTER_SSL_CERT = '" + params.SslCert + "'"
}
if params.SslKey != "" {
cmc += ",\n MASTER_SSL_KEY = '" + params.SslKey + "'"
}
return []string{
"STOP SLAVE",
"RESET SLAVE",
cmc,
"START SLAVE"}, nil
}
func (sq *SqlQuery) allowQueries(dbconfig *dbconfigs.DBConfig, schemaOverrides []SchemaOverride, qrs *QueryRules) {
sq.statemu.Lock()
v := sq.state.Get()
switch v {
case CONNECTING, ABORT, SERVING:
sq.statemu.Unlock()
log.Infof("Ignoring allowQueries request, current state: %v", v)
return
case INITIALIZING, SHUTTING_DOWN:
panic("unreachable")
}
// state is NOT_SERVING
sq.setState(CONNECTING)
sq.statemu.Unlock()
// Try connecting. disallowQueries can change the state to ABORT during this time.
waitTime := time.Second
for {
params, err := dbconfigs.MysqlParams(&dbconfig.ConnectionParams)
if err == nil {
c, err := mysql.Connect(params)
if err == nil {
c.Close()
break
}
log.Errorf("mysql.Connect() error: %v", err)
} else {
log.Errorf("dbconfigs.MysqlParams error: %v", err)
}
time.Sleep(waitTime)
// Cap at 32 seconds
if waitTime < 30*time.Second {
waitTime = waitTime * 2
}
if sq.state.Get() == ABORT {
// Exclusive transition. No need to lock statemu.
sq.setState(NOT_SERVING)
log.Infof("allowQueries aborting")
return
}
}
// Connection successful. Keep statemu locked.
sq.statemu.Lock()
defer sq.statemu.Unlock()
if sq.state.Get() == ABORT {
sq.setState(NOT_SERVING)
log.Infof("allowQueries aborting")
return
}
sq.setState(INITIALIZING)
defer func() {
if x := recover(); x != nil {
log.Errorf("%s", x.(*TabletError).Message)
sq.setState(NOT_SERVING)
return
}
sq.setState(SERVING)
}()
sq.qe.Open(&dbconfig.ConnectionParams, schemaOverrides, qrs)
sq.dbconfig = dbconfig
sq.sessionId = Rand()
log.Infof("Session id: %d", sq.sessionId)
}
func (sq *SqlQuery) allowQueries(dbconfig *dbconfigs.DBConfig, schemaOverrides []SchemaOverride, qrs *QueryRules, mysqld *mysqlctl.Mysqld) {
sq.statemu.Lock()
defer sq.statemu.Unlock()
v := sq.state.Get()
switch v {
case CONNECTING, ABORT, SERVING:
log.Infof("Ignoring allowQueries request, current state: %v", v)
return
case INITIALIZING, SHUTTING_DOWN:
panic("unreachable")
}
// state is NOT_SERVING
sq.setState(CONNECTING)
// When this function exits, state can be CONNECTING or ABORT
func() {
sq.statemu.Unlock()
defer sq.statemu.Lock()
waitTime := time.Second
// disallowQueries can change the state to ABORT during this time.
for sq.state.Get() != ABORT {
params, err := dbconfigs.MysqlParams(&dbconfig.ConnectionParams)
if err == nil {
c, err := mysql.Connect(params)
if err == nil {
c.Close()
break
}
log.Errorf("mysql.Connect() error: %v", err)
} else {
log.Errorf("dbconfigs.MysqlParams error: %v", err)
}
time.Sleep(waitTime)
// Cap at 32 seconds
if waitTime < 30*time.Second {
waitTime = waitTime * 2
}
}
}()
if sq.state.Get() == ABORT {
sq.setState(NOT_SERVING)
log.Infof("allowQueries aborting")
return
}
sq.setState(INITIALIZING)
defer func() {
if x := recover(); x != nil {
log.Errorf("%s", x.(*TabletError).Message)
sq.qe.Close()
sq.rci.Close()
sq.setState(NOT_SERVING)
return
}
sq.setState(SERVING)
}()
sq.qe.Open(dbconfig, schemaOverrides, qrs)
if dbconfig.EnableRowcache && dbconfig.EnableInvalidator {
sq.rci.Open(dbconfig.DbName, mysqld)
}
sq.dbconfig = dbconfig
sq.sessionId = Rand()
log.Infof("Session id: %d", sq.sessionId)
}
// OneRun tries a single cycle connecting to MySQL, and if behind on
// replication, starts playing the logs ahead to prime the cache.
func (pc *PrimeCache) OneRun() {
// connect to the database using dba for a control connection
params, err := dbconfigs.MysqlParams(&pc.dbcfgs.Dba)
if err != nil {
log.Errorf("Cannot get parameters to connect to MySQL: %v", err)
return
}
pc.dbConn, err = mysql.Connect(params)
if err != nil {
log.Errorf("mysql.Connect failed: %v", err)
return
}
// get the slave status
slavestat, err := pc.getSlaveStatus()
if err != nil {
log.Errorf("getSlaveStatus failed: %v", err)
return
}
// if we're not replicating, we're done
if !slavestat.slaveSQLRunning {
log.Errorf("Slave is not replicating (SQL)")
return
}
if !slavestat.slaveIORunning {
log.Errorf("Slave is not replicating (IO)")
return
}
if slavestat.secondsBehindMaster < 2 {
log.Errorf("Slave lag is negligible - %v seconds", slavestat.secondsBehindMaster)
return
}
// setup the connections to the db to apply the statements
if err := pc.setupPrimerConnections(); err != nil {
log.Errorf("setupPrimerConnections failed: %v", err)
return
}
// open the binlogs from where we are on
reader, err := pc.openBinlog(slavestat)
if err != nil {
log.Errorf("openBinlog failed: %v", err)
return
}
maxLineCount := 10000
var maxLeadBytes int64 = 5000000
// and start the loop
lineCount := 0
deleteCount := 0
appliedDeleteCount := 0
updateCount := 0
appliedUpdateCount := 0
sleepCount := 0
var logPos uint64
scanner := bufio.NewScanner(reader)
for scanner.Scan() {
line := scanner.Text()
lowerLine := strings.ToLower(line)
lineCount++
if p, isComment := parseLogPos(line); isComment {
// handle the comments with a log pos
if p > logPos {
logPos = p
}
} else if s, isDelete := parseDeleteStatement(line, lowerLine); isDelete {
// handle delete statements
deleteCount++
if s != "" {
appliedDeleteCount++
pc.workerChannel <- s
}
} else if s, isUpdate := parseUpdateStatement(line, lowerLine); isUpdate {
// handle update statements
updateCount++
if s != "" {
appliedUpdateCount++
pc.workerChannel <- s
}
}
if lineCount%maxLineCount == 0 {
var leadBytes int64
for {
slavestat, err = pc.getSlaveStatus()
if err != nil {
log.Errorf("getSlaveStatus failed: %v", err)
return
}
// see how far ahead we are (it's signed because
// we can be behind too)
leadBytes = int64(logPos) - int64(slavestat.execMasterLogPos)
if leadBytes > maxLeadBytes {
sleepCount++
log.Infof("Sleeping for 1 second waiting for SQL thread to advance: %v > %v", leadBytes, maxLeadBytes)
time.Sleep(1 * time.Second)
continue
} else {
break
}
}
log.Infof("STATS: readahead: %10d lag: %7d sleeps: %4d deletes: %10d missed updates: %10d updates: %10d\n",
leadBytes, slavestat.secondsBehindMaster, sleepCount, deleteCount, updateCount-appliedUpdateCount, appliedUpdateCount)
}
}
reader.Close()
if err := scanner.Err(); err != nil {
log.Errorf("Scanner failed: %v", err)
}
}