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situation can cause replication to fail. For more information, see Section 5.4.4.2, “Setting The Binary Log Format” . 

The binary log format affects the behavior of the following server options: 

• --replicate-do-db 

• --replicate-ignore-db 

• --binlog-do-db 

• --binlog-ignore-db 

These effects are discussed in detail in the descriptions of the individual options. 

• binlog_group_commit_sync_delay 

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Controls how many microseconds the binary log commit waits before synchronizing the binary log file to disk. By default binlog_group_commit_sync_delay  is set to 0, meaning that there is no delay. Setting binlog_group_commit_sync_delay  to a microsecond delay enables more transactions to be synchronized together to disk at once, reducing the overall time to commit a group of transactions because the larger groups require fewer time units per group. 

When sync_binlog=0  or sync_binlog=1  is set, the delay specified by binlog_group_commit_sync_delay  is applied for every binary log commit group before synchronization (or in the case of sync_binlog=0 , before proceeding). When sync_binlog  is set to a value n  greater than 1, the delay is applied after every n  binary log commit groups. 

Setting binlog_group_commit_sync_delay  can increase the number of parallel committing transactions on any server that has (or might have after a failover) a replica, and therefore can increase parallel execution on the replicas. To benefit from this effect, the replica servers must have slave_parallel_type=LOGICAL_CLOCK  set, and the effect is more significant when binlog_transaction_dependency_tracking=COMMIT_ORDER  is also set. It is important to take into account both the source’s throughput and the replicas’ throughput when you are tuning the setting for binlog_group_commit_sync_delay . 

Setting binlog_group_commit_sync_delay  can also reduce the number of fsync()  calls to the binary log on any server (source or replica) that has a binary log. 

Note that setting binlog_group_commit_sync_delay  increases the latency of transactions on the server, which might affect client applications. Also, on highly concurrent workloads, it is possible for the 

