In addition to having the use of log files and Transact-SQL statements, you will find a set of built-in functions that return system information. Here’s an overview of key built-in functions and their usages. The values returned by these functions are cumulative from the time SQL Server was last started.
Built-In Functions for Monitoring SQL Server Performance and Activity
| Function | Description | Example |
| @@connections | Returns the number of connections or attempted connections | select @@connections as 'Total Login Attempts' |
| @@cpu_busy | Returns CPU processing time in milliseconds for SQL Server activity | select @@cpu_busy as 'CPU Busy', getdate() as 'Since' |
| @@idle | Returns SQL Server idle time in milliseconds | select @@idle as 'Idle Time', getdate() as 'Since' |
| @@io_busy | Returns I/O processing time in milliseconds | select @@io_busy as 'IO Time', getdate() as 'Since' for SQL Server |
| @@pack_received | Returns the number of input packets read from the network by SQL Server | select @@pack_received as 'Packets Received' |
| @@pack_sent | Returns the number of output packets written to the network by SQL Server | select @@pack_sent as 'Packets Sent' |
| @@packet_errors | Returns the number of network packet errors for SQL Server connections | select @@packet_errors as 'Packet Errors' |
| @@timeticks | Returns the number of microseconds per CPU clock tick | select @@timeticks as 'Clock Ticks' |
| @@total_errors | Returns the number of disk read/write errors encountered by SQL Server | select @@total_errors as 'Total Errors', getdate() as 'Since' |
| @@total_read | Returns the number of disk reads by SQL Server | select @@total_read as 'Reads', getdate() as 'Since' |
| @@total_write | Returns the number of disk writes by SQL Server | select @@total_write as 'Writes', getdate() as 'Since' |
| fn_virtualfilestats | Returns input/output statistics for data and log files | select * from fn_virtualfilestats(null,null) |
1c63477d-858c-428b-b62f-4893cdec6031|0|.0