Replication and Binary Logging Options and Variables • --max-binlog-dump-events= N • --sporadic-binlog-dump-fail This option is used internally by the MySQL test suite for replication testing and debugging. Command-Line Format --max-binlog-dump-events=# Type Integer Default Value 0 Command-Line Format --sporadic-binlog-dump-fail[={OFF| ON}] Type Boolean Default Value OFF This option is used internally by the MySQL test suite for replication testing and debugging. The following list describes system variables for controlling binary logging. They can be set at server startup and some of them can be changed at runtime using  SET . Server options used to control binary logging are listed earlier in this section. System Variables Used with Binary Logging • binlog_cache_size The size of the memory buffer to hold changes to the binary log during a transaction. The value must be a multiple of 4096. When binary logging is enabled on the server (with the  log_bin  system variable set to ON), a binary log cache is allocated for each client if the server supports any transactional storage engines. If the data for the transaction exceeds the space in the memory buffer, the excess data is stored in a temporary file. When binary log encryption is active on the server, the memory buffer is not encrypted, but (from MySQL 8.0.17) any temporary file used to hold the binary log cache is encrypted. After each transaction is committed, the binary log cache is reset by clearing the memory buffer and truncating the temporary file if used. If you often use large transactions, you can increase this cache size to get better performance by reducing or eliminating the need to write to temporary files. The  Binlog_cache_use  and Command-Line Format --binlog-cache-size=# System Variable binlog_cache_size Scope Global Dynamic Yes SET_VAR  Hint Applies No Type Integer Default Value 32768 Minimum Value 4096 Maximum Value (64-bit platforms) 18446744073709547520 Maximum Value (32-bit platforms) 4294967295 Block Size 4096 3546