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辍学率非常缓慢
原标题:Mysql very slow on dropping indexes

我有专用服务器(Intel® CoreTM i7-2600) 等数。 高校对技术 16GBDR3, 2 x 3 TB SATA 6 Gb/s HDD 7200 rpm (Software-RAID 1) 并安装了 n变异的 n+apache+mysql。

我有一张200多万行的表格(大约400千米的数据)。 当我下降指数 d缩时,情况非常缓慢。 例如,我现在将一个单列的指数下降8分钟左右。 从一看,我有大约8Mb/sec。 这是否太缓慢?

问题回答

当你改变诺德语的表格(包括增加或降低指数)时,整个表格在磁盘上重写。 (数据抄本,索引重新编制)。 如果你在MySQL.1中使用InnoDB Plugin的话,那么这种情况就不会发生,但是由于缺席,MySQL.1不是与InnoDB Plugin建立起来的,而是与旧的InnoDB建立起来的。





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