To measure CPU utilization in a cloud-based architecture, or, to be specific, in a cluster (e.g., a Kubernetes cluster, Hadoop cluster, or any distributed system), you need to monitor CPU usage across all nodes in the cluster. Some people might be unaware of the cluster. A cluster is a collection of servers (virtual or physical) … Read more
Following are the Performance Engineering Interview Questions Set #15. Q. 71 How can you reduce the ‘Buffer Busy Waits’ identified in the AWR report? Ans: It can be reduced by: Q. 72 What are wait events in Oracle, and why are they important for performance analysis? Ans: Wait events represent the time sessions wait for … Read more
In AWR, the ‘Instance CPU’ table comes under the ‘Report Summary’ section. Refer to the below figure: To analyse the ‘Instance CPU’ section, you must Look at the Host CPU and Instance CPU sections. The key things to look for are the values “%Idle” in the “Host CPU” section and “%Total CPU” in the “Instance … Read more
In AWR, the ‘Host CPU’ table comes under the ‘Report Summary’ section. Refer to the below figure: The following metrics are available in the ‘Host CPU’ table of an AWR report: CPUs The number of CPUs is the product of the number of cores and threads available on the database server. Formula: CPU = Number … Read more
In AWR, the ‘Wait Classes by Total Wait Time’ table comes under the ‘Report Summary’ section. Refer to the below figure: To analyse this section, firstly check for the ‘Wait Class’ column. If User I/O, System I/O and Others have moderate ‘Waits’ value then it is fine. But if ‘Concurrency’ under the wait class has … Read more
In AWR, the ‘Top 10 Foreground Events’ table comes under the ‘Report Summary’ section. Refer to the below figure: The following metrics are available in the ‘Top 10 Foreground Events’ table of an AWR report: DB CPU It shows the total wait time for DB CPU and waiting %. Referring to Figure 01, the total … Read more