We collected the following database performance data through the Oracle database AWR report.
Based on the 30-minute AWR reports of a test case, the IOPS is the sum of physical read total I/O requests, per Second, and physical write total I/O requests, per Second, as shown in Figure 60.
Figure 60. Sample of IOPS measurement from AWR report
For an Oracle OLTP-style I/O workload, db file sequential read, the User I/O class wait is always the top wait event, accounting for most of the wait time. In this example, wait time averaged 0.443 milliseconds, as shown in Figure 61.
In addition to db file sequential read wait event, transaction redo logging write is another key performance indicator for Oracle OLTP-style I/O workloads. Figure 61 shows the top five timed events section of the AWR report from one of the OLTP production databases while the workload ran. In this example, wait time averaged 0.244 milliseconds.
For an Oracle OLAP-style I/O workload, the I/O MB/s throughput can be calculated as the physical read total I/O bytes per second, as shown in Figure 62. In this example, the I/O throughput is 591,947,981.72 bytes per second, or 564.52 MB/s.
The CPU utilization of the both database nodes is shown in the OS Statistics By Instance field of the AWR report, as shown in Figure 63.