Example: Output Tester
This is a tool I wrote to reproduce the recent problem(s) with the non-blocking commit patch. For me, it achieves this purpose readily every time. However, I feel this is also generally useful for more testing in the future.
Using keyboard commands, you can change display modes and enable/disable displays (one at a time or all of them together). I've tested this a lot on my 7-screen setup and it works quite well. However, the code is not designed to be especially robust or efficient. As usual, I look forward to any and all criticisms.
The keyboard commands are listed as comments at the top of the example source.