The I/O Activity tab on the Client Application Analysis drilldown provides a summary of I/O activity generated by the selected application. The graphs show rates for the following:
Reads and writes that use the buffer pool
Direct reads and writes, which do not go through the buffer pool, but access the database directly
The bottom of the tab lists average I/O times (in milliseconds) for both buffered and direct reads and writes. The average times are shown in milliseconds.
The graphs on the I/O Activity tab keep track of the rates for I/O generated by the application over consecutive monitoring intervals.
On the Databases drilldown, you might notice consistently high rates for the following activities on specific databases:
Physical read rates (compared to logical read rates)
Synchronous read or write rates
Direct I/O rates for a database
These high rates might be indications of performance degradation since the activities involve disk I/O and slow-downs in query processing. Use the graphs on this I/O Activity tab to identify the applications that are contributing to these rates.