本文探讨了一种常见的I/O分布优化误解，即频繁使用的表与其索引分离存储的方法并不总是有效。在事务处理过程中，索引与表数据的读取通常是顺序进行的，因此将它们放在同一磁盘上可以避免争用问题，提升数据库性能。
One popular approach to manual I/O distribution suggests separating a frequently used table from its index. This is not correct. During the course of a transaction, the index is read first, and then the table is read. Because these I/Os occur sequentially, the table and index can be stored on the same disk without contention. It is not sufficient to separate a datafile simply because the datafile contains indexes or table data. The decision to segregate a file should be made only when the I/O rate for that file affects database performance.
-- 引用自 <>
[@more@]来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/136097/viewspace-1007462/，如需转载，请注明出处，否则将追究法律责任。
转载于:http://blog.itpub.net/136097/viewspace-1007462/
扫一扫
被折叠的 条评论
为什么被折叠?
到【灌水乐园】发言
