Oracle 视图 V$IOFUNCMETRIC 官方解释，作用，如何使用详细说明

Oracle视图V$IOFUNCMETRIC是一个动态视图，可以用来查询统计当前操作系统性能度量指标，提供了函数文件I/O操作的度量数据，可以显示和求出每一个不同的I/O函数文件的性能指标，如开始到结束的时间，写或读的字节，读或写的次数等。

使用V$IOFUNCMETRIC，你可以查询或统计指定时间段内每一个不同的I/O函数文件的性能指标。SQL语句语法如下：

SELECT * FROM V$IOFUNCMETRIC WHERE START_TIM>=从某时间点开始；

V$IOFUNCMETRIC displays I/O statistics information by database function for the most recent time interval period.

Column	Datatype	Description
`BEGIN_TIME`	`DATE`	Begin time of the interval
`END_TIME`	`DATE`	End time of the interval
`INTSIZE_CSEC`	`NUMBER`	Interval size (in hundredths of a second)
`FUNCTION_ID`	`NUMBER`	Function ID
`FUNCTION_NAME`	`VARCHAR2(18)`	Function name
`SMALL_READ_MBPS`	`NUMBER`	Single block megabytes read per second
`SMALL_WRITE_MBPS`	`NUMBER`	Single block megabytes written per second
`LARGE_READ_MBPS`	`NUMBER`	Multiblock megabytes read per second
`LARGE_WRITE_MBPS`	`NUMBER`	Multiblock megabytes written per second
`SMALL_READ_IOPS`	`NUMBER`	Single block read requests per second
`SMALL_WRITE_IOPS`	`NUMBER`	Single block write requests per second
`LARGE_READ_IOPS`	`NUMBER`	Multiblock read requests per second
`LARGE_WRITE_IOPS`	`NUMBER`	Multiblock write requests per second
`AVG_WAIT_TIME`	`NUMBER`	Average wait time (in milliseconds)
`CON_ID`	`NUMBER`	The ID of the container to which the data pertains. Possible values include: `0`: This value is used for rows containing data that pertain to the entire CDB. This value is also used for rows in non-CDBs. `1`: This value is used for rows containing data that pertain to only the root n: Where n is the applicable container ID for the rows containing data