Make your redo log files big, even as big as the buffer pool. 让重做日志文件变大，甚至和缓冲池一样大。When InnoDB has written the redo log files full, it must write the modified contents of the buffer pool to disk in a checkpoint. 当InnoDB将重做日志文件写满后，它必须将缓冲池的修改内容写入检查点中的磁盘。Small redo log files cause many unnecessary disk writes. 小的重做日志文件会导致许多不必要的磁盘写入。Although historically big redo log files caused lengthy recovery times, recovery is now much faster and you can confidently use large redo log files.虽然历史上较大的重做日志文件会导致较长的恢复时间，但现在恢复速度要快得多，您可以放心地使用较大的重做日志文件。

The size and number of redo log files are configured using the innodb_log_file_size and innodb_log_files_in_group configuration options. 重做日志文件的大小和数量使用innodb_log_file_size和innodb_log_files_in_group配置选项进行配置。For information about modifying an existing redo log file configuration, see Changing the Number or Size of Redo Log Files.有关修改现有重做日志文件配置的信息，请参阅更改重做日志文件的数量或大小。

Consider increasing the size of the log buffer. 考虑增加日志缓冲区的大小。A large log buffer enables large transactions to run without a need to write the log to disk before the transactions commit. 大型日志缓冲区使大型事务能够运行，而无需在事务提交之前将日志写入磁盘。Thus, if you have transactions that update, insert, or delete many rows, making the log buffer larger saves disk I/O. 因此，如果您有更新、插入或删除多行的事务，那么增大日志缓冲区可以节省磁盘I/O。Log buffer size is configured using the innodb_log_buffer_size configuration option, which can be configured dynamically in MySQL 8.0.日志缓冲区大小使用innodb_Log_buffer_size配置选项进行配置，该选项可以在MySQL 8.0中动态配置。

Configure the innodb_log_write_ahead_size configuration option to avoid “read-on-write”. 配置innodb_log_write_ahead_size配置选项以避免“写时读”。This option defines the write-ahead block size for the redo log. 此选项定义重做日志的预写块大小。Set innodb_log_write_ahead_size to match the operating system or file system cache block size. 将innodb_log_write_ahead_size设置为与操作系统或文件系统缓存块大小匹配。Read-on-write occurs when redo log blocks are not entirely cached to the operating system or file system due to a mismatch between write-ahead block size for the redo log and operating system or file system cache block size.由于重做日志的预写块大小与操作系统或文件系统缓存块大小不匹配，重做日志块未完全缓存到操作系统或文件系统时，会发生读写。

Valid values for innodb_log_write_ahead_size are multiples of the InnoDB log file block size (2ⁿ). innodb_log_write_ahead_size的有效值是InnoDB日志文件块大小（2ⁿ）的倍数。The minimum value is the InnoDB log file block size (512). 最小值是InnoDB日志文件块大小（512）。Write-ahead does not occur when the minimum value is specified. 当指定最小值时，不会发生提前写入。The maximum value is equal to the innodb_page_size value. 最大值等于innodb_page_size值。If you specify a value for innodb_log_write_ahead_size that is larger than the innodb_page_size value, the innodb_log_write_ahead_size setting is truncated to the innodb_page_size value.如果为innodb_log_write_ahead_size指定的值大于innodb_page_size值，则innodb_log_write_ahead_size设置将被截断为innodb_page_size值。

Setting the innodb_log_write_ahead_size value too low in relation to the operating system or file system cache block size results in read-on-write. 将innodb_log_write_ahead_size值相对于操作系统或文件系统缓存块大小设置得太低会导致读写。Setting the value too high may have a slight impact on fsync performance for log file writes due to several blocks being written at once.由于同时写入多个块，将该值设置得过高可能会对日志文件写入的fsync性能产生轻微影响。

MySQL 8.0.11 introduced dedicated log writer threads for writing redo log records from the log buffer to the system buffers and flushing the system buffers to the redo log files. MySQL 8.0.11引入了专用的日志编写器线程，用于将重做日志记录从日志缓冲区写入系统缓冲区，并将系统缓冲区刷新到重做日志文件。Previously, individual user threads were responsible those tasks. 以前，单独的用户线程负责这些任务。As of MySQL 8.0.22, you can enable or disable log writer threads using the innodb_log_writer_threads variable. 从MySQL 8.0.22开始，可以使用innodb_log_writer_threads变量启用或禁用日志编写器线程。Dedicated log writer threads can improve performance on high-concurrency systems, but for low-concurrency systems, disabling dedicated log writer threads provides better performance.专用日志编写器线程可以提高高并发系统的性能，但对于低并发系统，禁用专用日志编写器线程可以提供更好的性能。

Optimize the use of spin delay by user threads waiting for flushed redo. 通过用户线程等待刷新重做来优化自旋延迟的使用。Spin delay helps reduce latency. 自旋延迟有助于减少延迟。During periods of low concurrency, reducing latency may be less of a priority, and avoiding the use of spin delay during these periods may reduce energy consumption. 在低并发期间，减少延迟可能不是重点，在这些期间避免使用自旋延迟可能会降低能耗。During periods of high concurrency, you may want to avoid expending processing power on spin delay so that it can be used for other work. 在高并发期间，您可能希望避免在自旋延迟上花费处理能力，以便它可以用于其他工作。The following system variables permit setting high and low watermark values that define boundaries for the use of spin delay.以下系统变量允许设置高水位线值和低水位线值，以定义使用自旋延迟的边界。