innodb新特性

6、innodb关键特性
6.1）插入缓冲(insert buffer)
条件：
辅助索引
没有唯一约束

    insert buffer

    change buffer
        innodb_change_buffer_max_size
        innodb_change_buffering
            inserts deletes purges changes all none

    merge insert buffer
        1、辅助索引页被读取到缓冲池时
        2、insert buffer bitmap页追踪到该索引页已无可用空间时
        3、master thread

6.2）两次写(double write)
    innodb_doublewrite
    Innodb_dblwr_pages_written
    Innodb_dblwr_writes

6.3）自适应hash索引(adaptive hash index)
    innodb_adaptive_flushing

6.4）异步Io(async IO)
    innodb_use_native_aio

6.5）刷新临接页(flush neighbor page)
    innodb_flush_neighbors