Replication and Binary Logging Options and Variables Dynamic Yes SET_VAR  Hint Applies No Type Integer Default Value 60 Minimum Value 1 Maximum Value 31536000 The number of seconds to wait for more data or a heartbeat signal from the source before the replica considers the connection broken, aborts the read, and tries to reconnect. Setting this variable has no immediate effect. The state of the variable applies on all subsequent  START REPLICA | SLAVE commands. The default value is 60 seconds (one minute). The first retry occurs immediately after the timeout. The interval between retries is controlled by the  SOURCE_CONNECT_RETRY  |  MASTER_CONNECT_RETRY option for the  CHANGE REPLICATION SOURCE TO  |  CHANGE MASTER TO  statement, and the number of reconnection attempts is limited by the  SOURCE_RETRY_COUNT  |  MASTER_RETRY_COUNT  option. The heartbeat interval, which stops the connection timeout occurring in the absence of data if the connection is still good, is controlled by the  SOURCE_HEARTBEAT_PERIOD  | MASTER_HEARTBEAT_PERIOD  option for the  CHANGE REPLICATION SOURCE TO  |  CHANGE MASTER TO  statement. The heartbeat interval defaults to half the value of  slave_net_timeout , and it is recorded in the replica’s connection metadata repository and shown in the replication_connection_configuration  Performance Schema table. Note that a change to the value or default setting of  slave_net_timeout  does not automatically change the heartbeat interval, whether that has been set explicitly or is using a previously calculated default. If the connection timeout is changed, you must also issue  CHANGE REPLICATION SOURCE TO  |  CHANGE MASTER TO  to adjust the heartbeat interval to an appropriate value so that it occurs before the connection timeout. For multithreaded replicas (replicas on which  slave_parallel_workers  is set to a value greater than 0),  slave_parallel_type  specifies the policy used to decide which transactions are allowed to execute in parallel on the replica. The variable has no effect on replicas for which multithreading is not enabled. The possible values are: 3532 • LOGICAL_CLOCK : Transactions that are part of the same binary log group commit on a source are applied in parallel on a replica. The dependencies between transactions are tracked based on their timestamps to provide additional parallelization where possible. When this value is set, the binlog_transaction_dependency_tracking  system variable can be used on the source to • slave_parallel_type Command-Line Format --slave-parallel-type=value System Variable slave_parallel_type Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Enumeration Default Value DATABASE Valid Values DATABASE LOGICAL_CLOCK