Parallel debuggers

TotalView supports TCL scripting very nicely. Had a nightmare system that consisted of 40+ interconnected processes. TotalView's tcl interface allowed me to create a script that attached to them all at once at startup in an automated fashion. Certain things would NOT have gotten fixed without that facility.

A colleague wrote a few years ago a short technical report comparing the two. Moral of the story: they're comparable, and the fact that there's competition in the market has improved the landscape considerably. We use DDT now; I prefer the interface, and it now scales to much larger process counts than totalview does (but I suspect totalview will make up the difference shortly). DDT also works on all our machines (x86, CUDA, Power); check to see if Totalview can cover all your platforms.