Chapter 2

1. What does it really mean when Apitrace preloads an instrumented implementation of OpenGL?
   This means exactly what is said here—Apitrace provides a DLL-implementing OpenGL functionality, which contains their tracing code. Preloading is a technique for loading a library manually, before the operating system has a chance to do so.
2. Isn't there a way to use gprof after all?
   Yes, of course. Just don't use threads, and link everything statically. You just have to add the appropriate switch (-pg) to qmake's compiler and link options, and maybe add gprof as external too.
   For simpler projects, this could perhaps be an option, but simpler projects normally don't have many performance problems, and if they do, a quick evaluation with Process Explorer would probably disclose their causes.

3. How would you look for a lock convoy or a waiting chain causing...