Tools and Utilities - Expert Oracle RAC Performance Diagnostics and Tuning - page 161

Figure 6-16. OSW: CPU context switches
The CPU usage maybe high because a process/session was engaged in traversing through large amounts of
data in the buffer cache, which caused high requests for latches, or the O/S parameters were not correctly set, which
caused a high context switch, which indirectly reflected on high CPU utilization (Figure 6-17 ) and this in turn made
the user session considerably slower.
Figure 6-17. OSW: CPU Utilization Chart
In this particular situation, a SQL statement was using high CPU due to large logical I/O operations (Figure 6-18 ).
Figure 6-18. OSW: CPU Interrupt Chart