Difference between ftrace and strace in Linux

Question

both strace and ftrace seem to be used for tracing function calls in Linux. What's the difference?

Answer 1

strace is a utility which allows you to trace the system calls that an application makes. When an application makes a system call, it is basically asking the kernel to do something, eg file access. Use the command man strace to get strace documentation and man syscalls to get information on system calls.

ftrace is a tool used during kernel development and allows the developer to see what functions are being called within the kernel. The documentation is here and states:

Ftrace is an internal tracer designed to help out developers and designers of systems to find what is going on inside the kernel. It can be used for debugging or analyzing latencies and performance issues that take place outside of user-space.