Note: Available for Oracle 10.2 and later.
The Services | Activity page provides an overview of the activity for services deployed on the Oracle RAC cluster.
To open the Activity page
- Select the Spotlight on Oracle RAC connection in the Spotlight Browser.
Click Services | Activity.
- Select a Service to view the activity for.
Charts on the Activity page
- Every chart has a legend (list of symbols) to its right that describes the various series (line graphs) on the chart.
- Click an item in the legend to highlight its series (line) in the chart. Click a second time to return the series to its normal appearance.
- Move the mouse pointer over an item in the legend to view the current value for that series within the chart.
For the selected service, Logical I/O shows the rate of logical database I/O on the Oracle RAC cluster. The chart shows the following data:
- Logical Reads - The rate (in IO/s) of logical reads for the Oracle RAC cluster.
- Block Changes - The number of database blocks in memory (SGA) that are modified per second.
For the selected service, Physical I/O shows I/O rates of physical reads and writes on the Oracle RAC cluster. The chart shows the following data:
- Physical Reads - The rate of reads from the datafiles, measured in disk I/O per second.
- Physical Writes - The rate of writes to the datafiles, measured in disk I/O per second.
For the selected service, Time Breakdown breaks down activity (in milliseconds per second) according to the following categories:
- Application - The rate at which time is spent on waits related to user application code.
- CPU - The rate at which time is spent in database user calls.
- Cluster - The rate at which time is spent on waits related to Oracle RAC resources.
- IO - The rate at which time is spent waiting for user I/O.
- Concurrency - The rate at which time is spent waiting for internal database resources.
For the selected service, Sessions shows the number of sessions connected to the database. The types of sessions are:
- Idle - Sessions that are not currently engaged in database activity.
- Active - Sessions that are currently performing some database activity.
For the selected service, Call Rates shows the rate of database calls made to all connected sessions. The call rates shown are:
- Parse - The rate at which requests to prepare SQL statements for execution are made to all connected sessions.
- Execute - The rate of executions made to all connected sessions in order to prepare a query to receive rows.
- Commit - The rate of Commit calls made to all connected sessions.
- Rollback - The rate of Rollback calls made to all connected sessions.
|Cluster Block Transfers
For the selected service, Cluster Block Transfers shows the rate of successful block transfers for CR (consistent read) blocks and current blocks between instances. The transfer rates shown are:
CR Blocks - The rate of transfer for consistent read blocks between instances.
A consistent read is a read from global cache for a block that is consistent at a point in time across all instances, and so keeps inserts or updates that occur during a query from changing the result.
When a consistent read requires access to rows that have changed since the query began, these rows are accessed from rollback segments.
Current Blocks - The rate of transfer for current blocks between instances.
A current read is a read from global cache of the most recently updated version of a data block. Current reads also occur for internal operations such as reading the header block during a table scan.