mysql innodb_force_recovery的各个恢复级别的参数说明

恢复级别参数说明：

1(SRV_FORCE_IGNORE_CORRUPT):忽略检查到的corrupt页。
2(SRV_FORCE_NO_BACKGROUND):阻止主线程的运行，如主线程需要执行full purge操作，会导致crash。
3(SRV_FORCE_NO_TRX_UNDO):不执行事务回滚操作。
4(SRV_FORCE_NO_IBUF_MERGE):不执行插入缓冲的合并操作。
5(SRV_FORCE_NO_UNDO_LOG_SCAN):不查看重做日志，InnoDB存储引擎会将未提交的事务视为已提交。
6(SRV_FORCE_NO_LOG_REDO):不执行前滚的操作。

 

源代码中的 注释说明：

enum {
    SRV_FORCE_IGNORE_CORRUPT = 1,   /*!< let the server run even if it
                    detects a corrupt page */
    SRV_FORCE_NO_BACKGROUND = 2,    /*!< prevent the main thread from
                    running: if a crash would occur
                    in purge, this prevents it */
    SRV_FORCE_NO_TRX_UNDO = 3,  /*!< do not run trx rollback after
                    recovery */
    SRV_FORCE_NO_IBUF_MERGE = 4,    /*!< prevent also ibuf operations:
                    if they would cause a crash, better
                    not do them */
    SRV_FORCE_NO_UNDO_LOG_SCAN = 5, /*!< do not look at undo logs when
                    starting the database: InnoDB will
                    treat even incomplete transactions
                    as committed */
    SRV_FORCE_NO_LOG_REDO = 6   /*!< do not do the log roll-forward
                    in connection with recovery */
};