`Innodb_log_file_size` is calculated as: (`innodb_os_log_written`-`innodb_os_log_written`(time shift -1h))/`{$MYSQL.INNODB_LOG_FILES}`. `Innodb_log_file_size` is the size in bytes of the each InnoDB redo log file in the log group. The combined size can be no more than 512 GB. Larger values mean less disk I/O due to less flushing checkpoint activity, but also slower recovery from a crash.