Capgemini Interview Questions and Answers

Scenarios where issues with heap dump occur and recommendations for dev team

• Heap dump size is too large

• Heap dump is not generated at the right time

• Heap dump is not analyzed properly

• Heap dump is not shared with the right team members

• Recommendations: Optimize code to reduce memory usage, generate heap dump at appropriate times, analyze heap dump thoroughly, share heap dump with relevant team members

To gather NFR from an unaware client for a new application, follow these steps:

• Explain the importance of performance testing and its benefits

• Provide examples of how performance issues can impact the application and business

• Ask the client about their expectations for the application's performance

• Discuss the application's usage scenarios and expected user load

• Collaborate with the development team to identify potential performance bottlenecks

• Use industry standards and best pract...read more

Thread dumps are analyzed to identify performance bottlenecks and deadlocks in the application.

• To identify the root cause of performance issues

• To identify deadlocks and thread contention issues

• To identify long running threads and blocked threads

• To identify memory leaks and excessive CPU usage

• To identify issues related to garbage collection

• To identify issues related to database connections and transactions

Yes, virtual users can be reinitialized if they go to error state with consumable data.

• Reinitializing virtual users can help in identifying the root cause of the error.

• It is important to ensure that the consumable data is backed up before reinitializing the virtual users.

• Reinitializing virtual users should be done only after analyzing the error and identifying the cause.

• It is important to have a backup plan in case reinitializing the virtual users does not resolve the error.

Context switching and parsing are database operations that impact DB server performance.

• Context switching is the process of switching between different tasks or threads in a CPU.

• Parsing is the process of analyzing and interpreting data in a database.

• Both operations require CPU resources and can cause delays in processing other tasks.

• Context switching can be reduced by optimizing code and minimizing the number of threads.

• Parsing can be improved by using efficient algorithms an...read more

Generating heap dump and thread dump on Unix/Linux systems

• For heap dump: use jmap command with -dump option

• For thread dump: use jstack command

• Heap dump can also be generated using kill -3

• Thread dump can also be generated using kill -QUIT

Thread states in thread dump include NEW, RUNNABLE, BLOCKED, WAITING, TIMED_WAITING, and TERMINATED.

• NEW: thread has been created but not yet started

• RUNNABLE: thread is executing or ready to execute

• BLOCKED: thread is blocked waiting for a monitor lock

• WAITING: thread is waiting indefinitely for another thread to perform a particular action

• TIMED_WAITING: thread is waiting for another thread to perform a particular action for a specified period of time

• TERMINATED: thread has compl...read more

I have used various tools for DB server tuning such as SQL Profiler, SQL Server Management Studio, and Database Engine Tuning Advisor.

• SQL Profiler for monitoring and analyzing SQL Server activity

• SQL Server Management Studio for managing and configuring SQL Server instances

• Database Engine Tuning Advisor for analyzing workload and recommending index and partitioning strategies