8.3.2. Profiling Kernel-Space Code

Try these first

1. 1.

   What does ftrace do?

   Hint

   Think about tracing and measurement in the kernel.

2. 2.

   What command initiates perf to record performance data?

   Hint

   Focus on the startup command for performance.

3. 3.

   What is the purpose of ftrace?

   • Network analysis
   • Tracing kernel functions
   • Managing memory

   Hint

   Think about what tracing specifically relates to.

4. 4.

   True or False: perf can only be used for user-space applications.

   • True
   • False

   Hint

   Consider the abilities of the perf tool.

5. 5.

   Write a SystemTap script that tracks all disk read operations happening in real-time and outputs the result to a log file.

   Hint

   Focus on identifying the correct probes to track disk activity.

6. 6.

   Analyze how the overhead induced by perf affects the performance of a kernel application during profiling.

   Hint

   Think about how profiling may impact system response times.