1、sys.dm_io_virtual_file_stats
SELECT DB_NAME(vfs.database_id) AS database_name , vfs.database_id , vfs.FILE_ID , io_stall_read_ms / NULLIF(num_of_reads, 0) AS avg_read_latency , io_stall_write_ms / NULLIF(num_of_writes, 0) AS avg_write_latency , io_stall / NULLIF(num_of_reads + num_of_writes, 0) AS avg_total_latency , num_of_bytes_read / NULLIF(num_of_reads, 0) AS avg_bytes_per_read , num_of_bytes_written / NULLIF(num_of_writes, 0) AS avg_bytes_per_write , vfs.io_stall , vfs.num_of_reads , vfs.num_of_bytes_read , vfs.io_stall_read_ms , vfs.num_of_writes , vfs.num_of_bytes_written , vfs.io_stall_write_ms , size_on_disk_bytes / 1024 / 1024. AS [size_on_disk_mbytes(MB)] , mf.physical_name FROM sys.dm_io_virtual_file_stats(DB_ID('master'), 1) AS vfs JOIN sys.master_files AS mf ON vfs.database_id = mf.database_id AND vfs.FILE_ID = mf.FILE_ID ORDER BY avg_total_latency DESC |
如果sys.dm_io_virtual_file_stats(null,null)那么会显示所有默认数据库和曾经附加过的数据库的信息，这里只想看master数据库的I/O信息，对数据库上执行后结果分析如下：
2、sys.dm_io_cluster_shared_drives和sys.dm_io_cluster_valid_path_names
如果你的数据库架构采用了集群部署，那么可以通过这两个查到关于集群节点的信息。未来sys.dm_io_cluster_shared_drives将被废弃，采用sys.dm_io_cluster_valid_path_names代替。
