SQL Server keeps track of all the reads and writes it submits to the operating system (OS). It records this information in sys.dm_io_virtual_file_stats DMF. We
Tag: DMF – sys.dm_io_virtual_file_stats
Getting file usage stats
You can use this DMV to see what SQL Server thinks about the I/O stall times. I don’t rely on it 100% but it helpful
SQL Canada (SQLCAN) 