Performance Engineering Interview Questions #17

Performance Engineering Interview Questions 17

Following are the Performance Engineering Interview Questions Set #17. Q. 81 Is a high buffer cache hit ratio always indicative of good performance? Ans: Not necessarily. While a high hit ratio means most data requests are served from memory, it doesn’t account for inefficient queries or unnecessary data access patterns. It’s important to look at … Read more

Performance Engineering Interview Questions #16

Performance Engineering Interview Questions 16

Following are the Performance Engineering Interview Questions Set #16. Q. 76 Explain the “latch: cache buffers chains” wait event and its impact. Ans: This wait event indicates contention for cache buffer chain latches, which protect the hash chains of buffer headers in the buffer cache. High waits suggest hot blocks or heavy concurrent access to … Read more

Performance Engineering Interview Questions #15

Performance Engineering Interview Question 15

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

Performance Engineering Interview Questions #14

Performance Engineering Interview Questions 14

Following are the Performance Engineering Interview Questions Set #14. Q. 66 What is the difference between ‘db file sequential read’ and ‘db file scattered read’ wait events? Ans: The ‘db file sequential read’ indicates single-block reads, often associated with index lookups whereas ‘db file scattered read’ involves multi-block reads, typically from full table scans or … Read more

Free Performance Testing Video Tutorials

Free Performance Testing Video Tutorials

Many free videos and learning tutorials related to Performance Testing are available on YouTube. Some video series are specific to performance testing and APM tools and share in-depth knowledge free of cost. Below are the links for those tutorials:  Basics: Tools: APM Tools:

AWR – Instance CPU

AWR - Instance CPU

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