I've been spending a lot of time profiling DRI drivers for Gallium 3D. I've tried gprof, valgrind, and finally oprofile. Oprofile seems the best in my opinion for this purpose. More details on the DRI Wiki.
I also wrote a script to generate a time-colored call graph from oprofile output, using graphviz. See an output example of profiling glxgears on Gallium 3D:
The hotter the colour of a function is, more time is spent on that function and its children.
I've never learned to use Emacs. I love vim, but it doesn't scale for me when editing more than three files at the same time or projects with more than one directory. After two years using Eclipse for Python and Windows C++ development, I've been using almost exclusively Eclipse for X.Org/Mesa/DRI development during the last three months.
I think Eclipse is really a pleasant development environment:
Also, the CDT (the C/C++ Development Plugin for Eclipse) folks are now actively working to get Eclipse not only to debug remote applications, but also build remotely, which will greatly simplify testing on multiple software/hardware configurations.
The thing I miss the most is better git integration. Of course, it is advisable to have a big screen and lots of memory.
For those interested, I've wrote some instructions to get you started on the X.Org Wiki.
In Debian/Ubuntu, when logging from gdm your ~/.bash_profile or even ~/.bash_rc are loaded, preventing you to set environment variables for all your session. The reason is that gdm starts /usr/bin/x-session-manager directly.
There are many ways to get ~/.bash_profile loaded. Many of which are wrong.
I found that a very simple way to loading ~/.bash_profile when starting X is to write the following ~/.xsession script:
#!/bin/bash --login exec /usr/bin/x-session-manager
