16.2.3.3 Startup Options and Replication Channels

This section describes startup options which are impacted by the addition of replication channels.

The following startup settings must be configured correctly to use multi-source replication.

The following startup options now affect all channels in a replication topology.

The values set for the following startup options apply on each channel; since these are mysqld startup options, they are applied on every channel.

  • --max-relay-log-size=size

    Maximum size of the individual relay log file for each channel; after reaching this limit, the file is rotated.

  • --relay-log-space-limit=size

    Upper limit for the total size of all relay logs combined, for each individual channel. For N channels, the combined size of these logs is limited to relay_log_space_limit * N.

  • --slave-parallel-workers=value

    Number of worker threads per channel.

  • slave_checkpoint_group

    Waiting time by an I/O thread for each source.

  • --relay-log-index=filename

    Base name for each channel's relay log index file. See Section 16.2.3.4, “Replication Channel Naming Conventions”.

  • --relay-log=filename

    Denotes the base name of each channel's relay log file. See Section 16.2.3.4, “Replication Channel Naming Conventions”.

  • --slave_net-timeout=N

    This value is set per channel, so that each channel waits for N seconds to check for a broken connection.

  • --slave-skip-counter=N

    This value is set per channel, so that each channel skips N events from its source.